ci: disable errorprone during "tests" job (#15312)

Errorprone is only needed for "checks without tests". The idea is to
speed up compilation for the "tests" job, which focuses on executing
tests. Any errorprone issues will be found by the "checks without tests"
job.

Author: rmuir

.github/workflows/run-checks-all.yml

@@ -88,7 +88,7 @@ jobs:
         uses: ./.github/actions/prepare-for-build
 
       - name: Run gradle tests
-        run: ./gradlew test "-Ptask.times=true" --max-workers 2
+        run: ./gradlew test "-Ptask.times=true" "-Pvalidation.errorprone=false" --max-workers 2
 
       - name: List automatically-initialized gradle.properties
         run: cat gradle.properties

build-tools/build-infra/src/main/java/org/apache/lucene/gradle/plugins/java/ErrorPronePlugin.java

@@ -100,8 +100,7 @@ public void apply(Project project) {
           skipReason = null;
         } else {
           if (buildGlobals.isCIBuild) {
-            throw new GradleException(
-                "Odd, errorprone linting should always be enabled on CI builds?");
+            skipReason = "skipped explicitly on a CI build it seems";
           } else {
             skipReason =
                 "skipped on builds not running inside CI environments, pass -P"