Update Gitiles bazel version to 7.6.1 (matches JGit & Gerrit)

Also fix bazel's jdk tool registrations to match JGit & Gerrit.

Change-Id: Iec03b7e28a8d20f49f27eb399c855cf4ffda7245

.bazelversion

diff --git a/.bazelversion b/.bazelversion
index 9fe9ff9..e8be684 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-7.0.1
+7.6.1

tools/BUILD

diff --git a/tools/BUILD b/tools/BUILD
index 8ea3629..004f1c3 100644
--- a/tools/BUILD
+++ b/tools/BUILD
@@ -8,7 +8,7 @@
     name = "error_prone_warnings_toolchain_java17",
 
     configuration = dict(),
-    java_runtime = "@bazel_tools//tools/jdk:remotejdk_17",
+    java_runtime = "@rules_java//toolchains:remotejdk_17",
     package_configuration = [
         ":error_prone",
     ],
@@ -21,7 +21,7 @@
     name = "error_prone_warnings_toolchain_java21",
 
     configuration = dict(),
-    java_runtime = "@bazel_tools//tools/jdk:remotejdk_21",
+    java_runtime = "@rules_java//toolchains:remotejdk_21",
     package_configuration = [
         ":error_prone",
     ],