fix(bake): Bake stage output may contain output from unrelated stages (…

…#3652)

As @luispollo notes in the code I removed, the current implementation may include output from completely unrelated bakes that are running at the same time as the bake stage in question. I fail to see any reason this can be correct.

After applying this fix, each bake stage will contain the bakes created in that bake stage, and nothing else.

Coupled with [this PR](#3651), this fix will make the output of pipelines with multiple bake stages correct, as all the `deploymentDetails` will be merged instead of overwritten, and thus contain all images created, and not just an arbitrary list which is timing dependent.

Co-authored-by: Mark Vulfson <mvulfson@netflix.com>

orca-bakery/src/main/groovy/com/netflix/spinnaker/orca/bakery/pipeline/BakeStage.groovy

@@ -142,15 +142,8 @@ class BakeStage implements StageDefinitionBuilder {
 
     @Nonnull
     TaskResult execute(@Nonnull StageExecution stage) {
-      def bakeInitializationStages = stage.execution.stages.findAll {
-        it.parentStageId == stage.parentStageId && it.status == ExecutionStatus.RUNNING
-      }
-
-      // FIXME? (lpollo): I don't know why we do this, but we include in relatedStages all parallel bake stages in the
-      //  same pipeline, not just the ones related to the stage passed to this task, which means this list actually
-      //  contains *unrelated* bake stages...
       def relatedBakeStages = stage.execution.stages.findAll {
-        it.type == PIPELINE_CONFIG_TYPE && bakeInitializationStages*.id.contains(it.parentStageId)
+        it.type == PIPELINE_CONFIG_TYPE && stage.id == it.parentStageId
       }
 
       def globalContext = [