Bazel: Remove explicit java_toolchain option

Java toolchain is specified in .bazelrc file in gerrit workspace and
thus shouldn't be specified explicitly.

On master branch Bazel was updated to release 5.0, and the explicit
toolchain option is ignored anyway. On stable-3.5 branch, the code was
migrated to Java 11 language level, and hence toolchain_java8 was
removed and the build is failing for plugins on this branch.

Also remove verification jobs for discontinued stable branches and add
verification jobs for supported stable branches.

Bug: Issue 15509
Change-Id: I97dc38f4bf19f57f84e24d850d22909e73f0293b

roles/bazelisk-build/tasks/main.yaml

diff --git a/roles/bazelisk-build/tasks/main.yaml b/roles/bazelisk-build/tasks/main.yaml
index c65f54e..3bc6c7f 100644
--- a/roles/bazelisk-build/tasks/main.yaml
+++ b/roles/bazelisk-build/tasks/main.yaml
@@ -2,14 +2,14 @@
   shell: |
     java -fullversion
     {{ bazelisk_executable }} version
-    {{ bazelisk_executable }} build --java_toolchain=//tools:error_prone_warnings_toolchain {{ bazelisk_targets }}
+    {{ bazelisk_executable }} build {{ bazelisk_targets }}
   args:
     executable: /bin/bash
     chdir: "{{ zuul_work_dir }}"
 - name: Run bazelisk test
   when: "bazelisk_test_targets != ''"
   shell: |
-    {{ bazelisk_executable }} test --java_toolchain=//tools:error_prone_warnings_toolchain --test_output=errors --test_summary=detailed --flaky_test_attempts=3 {{ bazelisk_test_targets }}
+    {{ bazelisk_executable }} test --test_output=errors --test_summary=detailed --flaky_test_attempts=3 {{ bazelisk_test_targets }}
   args:
     executable: /bin/bash
     chdir: "{{ zuul_work_dir }}"

zuul.d/project.yaml

diff --git a/zuul.d/project.yaml b/zuul.d/project.yaml
index 41c8331..12c9c7c 100644
--- a/zuul.d/project.yaml
+++ b/zuul.d/project.yaml
@@ -7,8 +7,6 @@
         - test-install-build-essential
         - test-gerrit-plugin-build
         - test-gerrit-build-master
+        - test-gerrit-build-stable-3.5
+        - test-gerrit-build-stable-3.4
         - test-gerrit-build-stable-3.3
-        - test-gerrit-build-stable-3.2
-        - test-gerrit-build-stable-3.1
-        - test-gerrit-build-stable-3.0
-        - test-gerrit-build-stable-2.16

zuul.d/test-jobs.yaml

diff --git a/zuul.d/test-jobs.yaml b/zuul.d/test-jobs.yaml
index 7015165..9f082ee 100644
--- a/zuul.d/test-jobs.yaml
+++ b/zuul.d/test-jobs.yaml
@@ -71,26 +71,16 @@
       - playbooks/gerrit/.*
 
 - job:
+    name: test-gerrit-build-stable-3.5
+    parent: test-gerrit-build-master
+    override-checkout: stable-3.5
+
+- job:
+    name: test-gerrit-build-stable-3.4
+    parent: test-gerrit-build-master
+    override-checkout: stable-3.4
+
+- job:
     name: test-gerrit-build-stable-3.3
     parent: test-gerrit-build-master
     override-checkout: stable-3.3
-
-- job:
-    name: test-gerrit-build-stable-3.2
-    parent: test-gerrit-build-master
-    override-checkout: stable-3.2
-
-- job:
-    name: test-gerrit-build-stable-3.1
-    parent: test-gerrit-build-master
-    override-checkout: stable-3.1
-
-- job:
-    name: test-gerrit-build-stable-3.0
-    parent: test-gerrit-build-master
-    override-checkout: stable-3.0
-
-- job:
-    name: test-gerrit-build-stable-2.16
-    parent: test-gerrit-build-master
-    override-checkout: stable-2.16