Repeat the change we did in bazelbuild@2bba03b.

It was accidentally overridden in bazelbuild@3f8bab9.

PiperOrigin-RevId: 549600680
Change-Id: Ibac001901332c99aacc60eb1c01fd2231eb787f2

src/main/java/com/google/devtools/build/lib/actions/SpawnMetrics.java

@@ -38,7 +38,7 @@ public class SpawnMetrics {
     this.setupTimeInMs = builder.setupTimeInMs;
     this.uploadTimeInMs = builder.uploadTimeInMs;
     this.executionWallTimeInMs = builder.executionWallTimeInMs;
-    this.retryTimeInMs = builder.retryTimeInMs;
+    this.retryTimeInMs = ImmutableMap.copyOf(builder.retryTimeInMs);
     this.processOutputsTimeInMs = builder.processOutputsTimeInMs;
     this.inputBytes = builder.inputBytes;
     this.inputFiles = builder.inputFiles;
@@ -79,7 +79,7 @@ public String toString() {
   int processOutputsTimeInMs;
   int networkTimeInMs;
   // error code to duration in ms
-  Map<Integer, Integer> retryTimeInMs;
+  ImmutableMap<Integer, Integer> retryTimeInMs;
   long inputBytes;
   long inputFiles;
   long memoryEstimateBytes;