Use the default C++ toolchain for RBE instead of rbe_autoconfig

JGit is a pure-Java project and schedules no C++ compile actions, so
the RBE C++ toolchain is never invoked; it only has to exist to
satisfy analysis-time resolution of
@bazel_tools//tools/cpp:toolchain_type (used by ijar/zipper in the
Java rules).

Drop the @rbe_autoconfig crosstool_top and extra_toolchains flags and
rely on Bazel's built-in autodetected C++ toolchain, which resolves on
the Linux CI host and is never run. The RBE execution container is
still pinned explicitly: a minimal platform in tools/remote/BUILD
names the container via the container-image exec property, which is
what actually selects it, not the C++ toolchain. This also updates the
container from ubuntu2204 to the current gcr.io/bazel-public/ubuntu2404
image, matching Gerrit. Bumping the image is now a one-line digest edit
rather than regenerating configs with rbe_configs_gen.

This removes the dependency on the rbe_autoconfig module, and the
bazel-toolchains / rbe_configs_gen tooling behind it, entirely.

Change-Id: Icf4c40cf83a8451263fef03d18eb58b937b3e796
Signed-off-by: David Ostrovsky <david@ostrovsky.org>

MODULE.bazel

diff --git a/MODULE.bazel b/MODULE.bazel
index 843d08e..c873b13 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -1,17 +1,12 @@
 module(name = "jgit")
 
 bazel_dep(name = "bazel_features", version = "1.42.1")
+bazel_dep(name = "platforms", version = "1.1.0")
 bazel_dep(name = "rules_android", version = "0.7.1")
 bazel_dep(name = "rules_go", version = "0.60.0")
 bazel_dep(name = "rules_java", version = "9.3.0")
 bazel_dep(name = "rules_jvm_external", version = "6.10")
 bazel_dep(name = "rules_shell", version = "0.6.1")
-bazel_dep(name = "rbe_autoconfig")
-git_override(
-    module_name = "rbe_autoconfig",
-    commit = "71f39817c028949bd6d25f1806502bcd33028d14",
-    remote = "https://github.com/davido/rbe_autoconfig.git",
-)
 
 register_toolchains("//tools:error_prone_warnings_toolchain_java17_definition")
 

MODULE.bazel.lock

diff --git a/MODULE.bazel.lock b/MODULE.bazel.lock
index da5f702..7d473fc 100644
--- a/MODULE.bazel.lock
+++ b/MODULE.bazel.lock
@@ -100,7 +100,8 @@
     "https://bcr.bazel.build/modules/platforms/0.0.8/MODULE.bazel": "9f142c03e348f6d263719f5074b21ef3adf0b139ee4c5133e2aa35664da9eb2d",
     "https://bcr.bazel.build/modules/platforms/0.0.9/MODULE.bazel": "4a87a60c927b56ddd67db50c89acaa62f4ce2a1d2149ccb63ffd871d5ce29ebc",
     "https://bcr.bazel.build/modules/platforms/1.0.0/MODULE.bazel": "f05feb42b48f1b3c225e4ccf351f367be0371411a803198ec34a389fb22aa580",
-    "https://bcr.bazel.build/modules/platforms/1.0.0/source.json": "f4ff1fd412e0246fd38c82328eb209130ead81d62dcd5a9e40910f867f733d96",
+    "https://bcr.bazel.build/modules/platforms/1.1.0/MODULE.bazel": "1c0c09f5bdcf4b3f924720d2478a3711cb39f4977019ca5988685e5b7e18b3d2",
+    "https://bcr.bazel.build/modules/platforms/1.1.0/source.json": "fcf351c47596c939140ab0d333dfdd08ed1ea6ce33c2fe70c12493a301cf1344",
     "https://bcr.bazel.build/modules/protobuf/21.7/MODULE.bazel": "a5a29bb89544f9b97edce05642fac225a808b5b7be74038ea3640fae2f8e66a7",
     "https://bcr.bazel.build/modules/protobuf/23.1/MODULE.bazel": "88b393b3eb4101d18129e5db51847cd40a5517a53e81216144a8c32dfeeca52a",
     "https://bcr.bazel.build/modules/protobuf/24.4/MODULE.bazel": "7bc7ce5f2abf36b3b7b7c8218d3acdebb9426aeb35c2257c96445756f970eb12",

tools/remote-bazelrc

diff --git a/tools/remote-bazelrc b/tools/remote-bazelrc
index 39797b8..b5654f9 100644
--- a/tools/remote-bazelrc
+++ b/tools/remote-bazelrc
@@ -30,11 +30,9 @@
 
 # Set several flags related to specifying the platform, toolchain and java
 # properties.
-build:remote --crosstool_top=@rbe_autoconfig//cc:toolchain
-build:remote --extra_toolchains=@rbe_autoconfig//config:cc-toolchain
-build:remote --extra_execution_platforms=@rbe_autoconfig//config:platform
-build:remote --host_platform=@rbe_autoconfig//config:platform
-build:remote --platforms=@rbe_autoconfig//config:platform
+build:remote --extra_execution_platforms=//tools/remote:platform
+build:remote --host_platform=//tools/remote:platform
+build:remote --platforms=//tools/remote:platform
 
 # Set various strategies so that all actions execute remotely. Mixing remote
 # and local execution will lead to errors unless the toolchain and remote

tools/remote/BUILD

diff --git a/tools/remote/BUILD b/tools/remote/BUILD
new file mode 100644
index 0000000..f891215
--- /dev/null
+++ b/tools/remote/BUILD
@@ -0,0 +1,17 @@
+# RBE execution platform. Names the container Bazel actions run in on the
+# remote executor. JGit is pure Java and schedules no C++ actions, so the
+# default (autodetected) cc toolchain satisfies analysis-time resolution
+# and is never invoked; only this platform, naming the container image,
+# is needed -- there is no generated CROSSTOOL to maintain.
+platform(
+    name = "platform",
+    constraint_values = [
+        "@platforms//cpu:x86_64",
+        "@platforms//os:linux",
+    ],
+    exec_properties = {
+        "OSFamily": "Linux",
+        "container-image": "docker://gcr.io/bazel-public/ubuntu2404@sha256:57bbaa84bec679736c53dcd1d326e8f835b3b9ce3e36c12a3c12a07eb59177d3",
+    },
+    visibility = ["//visibility:public"],
+)