Catch more build failures in job summary (#571)

By inspecting a greater range of build operations for failure, the Job
summary will correctly reflect the build outcome in more circumstances.

Note that we now use the old 'buildFinished' mechanism for all Gradle
versions < `7.0`, instead of using the BuildService mechanism for all
Gradle versions from `6.6`. This avoids needing to deal with
inconsistent build operations present in Gradle versions `[6.6, 7.0)`.

Fixes #415

sources/src/resources/init-scripts/gradle-actions.build-result-capture-service.plugin.groovy

@@ -41,10 +41,8 @@ abstract class BuildResultsRecorder implements BuildService<BuildResultsRecorder
             // Got EVALUATE SETTINGS event: not a config-cache hit"
             configCacheHit = false
         }
-        if (buildOperation.details in RunRootBuildWorkBuildOperationType.Details) {
-            if (finishEvent.failure != null) {
-                buildFailed = true
-            }
+        if (finishEvent.failure != null) {
+            buildFailed = true
         }
     }