Fix E2E tests: skip on single-region emulator

Read and write barrier requests are only triggered on multi-region strong
consistency accounts (numberOfReadRegions > 0). The emulator is single-region,
so the GCLSN interceptor never triggers barriers and the tests fail with
empty supplementalResponseStatisticsList.

Added accountLevelReadRegions.size() > 1 skip check to all three E2E fault
injection tests so they correctly skip on single-region environments.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: mbhaskar

sdk/cosmos/azure-cosmos-tests/src/test/java/com/azure/cosmos/faultinjection/FaultInjectionServerErrorRuleOnDirectTests.java

@@ -1821,11 +1821,17 @@ private static boolean isOperationAWriteOperation(OperationType operationType) {
     public void faultInjection_readBarrierThrottled_yieldsEarly() throws JsonProcessingException {
         // Validates that when barrier HEAD requests are throttled (429) during a strong read,
         // the early yield mechanism fires and the 429 is propagated to the caller.
+        // This test requires a multi-region strong consistency account because read barriers
+        // are only triggered when numberOfReadRegions > 0.
 
         if (this.databaseAccount.getConsistencyPolicy().getDefaultConsistencyLevel() != ConsistencyLevel.STRONG) {
             throw new SkipException("Test only applicable to STRONG consistency level.");
         }
 
+        if (this.accountLevelReadRegions.size() <= 1) {
+            throw new SkipException("Test requires multi-region account for read barriers to be triggered.");
+        }
+
         CosmosAsyncClient newClient = null;
         String faultInjectionRuleId = "barrier-429-read-yield-" + UUID.randomUUID();
         FaultInjectionRule barrierThrottleRule =
@@ -1900,6 +1906,10 @@ public void faultInjection_writeBarrierThrottled_returns408() throws JsonProcess
             throw new SkipException("Test only applicable to STRONG consistency level.");
         }
 
+        if (this.accountLevelReadRegions.size() <= 1) {
+            throw new SkipException("Test requires multi-region account for write barriers to be triggered.");
+        }
+
         CosmosAsyncClient newClient = null;
         String faultInjectionRuleId = "barrier-429-write-408-" + UUID.randomUUID();
         FaultInjectionRule barrierThrottleRule =
@@ -1973,6 +1983,10 @@ public void faultInjection_readBarrierThrottled_thenRecovers() throws JsonProces
             throw new SkipException("Test only applicable to STRONG consistency level.");
         }
 
+        if (this.accountLevelReadRegions.size() <= 1) {
+            throw new SkipException("Test requires multi-region account for read barriers to be triggered.");
+        }
+
         CosmosAsyncClient newClient = null;
         String faultInjectionRuleId = "barrier-429-recover-" + UUID.randomUUID();
         FaultInjectionRule barrierThrottleRule =