chore(spanner): increase backup operation timeout in samples to 3600s (#14033)

Author: sakthivelmanii

java-spanner/samples/snippets/src/main/java/com/example/spanner/CreateBackupWithEncryptionKey.java

@@ -83,7 +83,7 @@ static Void createBackupWithEncryptionKey(DatabaseAdminClient adminClient,
                     .setKmsKeyName(kmsKeyName).build()).build();
     try {
       System.out.println("Waiting for operation to complete...");
-      backup = adminClient.createBackupAsync(request).get(1200, TimeUnit.SECONDS);
+      backup = adminClient.createBackupAsync(request).get(3600, TimeUnit.SECONDS);
     } catch (ExecutionException e) {
       // If the operation failed during execution, expose the cause.
       throw SpannerExceptionFactory.asSpannerException(e.getCause());

java-spanner/samples/snippets/src/main/java/com/example/spanner/CreateBackupWithMultiRegionEncryptionKey.java

@@ -95,7 +95,7 @@ static Void createBackupWithMultiRegionEncryptionKey(
             .build();
     try {
       System.out.println("Waiting for operation to complete...");
-      backup = adminClient.createBackupAsync(request).get(1200, TimeUnit.SECONDS);
+      backup = adminClient.createBackupAsync(request).get(3600, TimeUnit.SECONDS);
     } catch (ExecutionException e) {
       // If the operation failed during execution, expose the cause.
       throw SpannerExceptionFactory.asSpannerException(e.getCause());

java-spanner/samples/snippets/src/main/java/com/example/spanner/admin/archived/CreateBackupWithEncryptionKey.java

@@ -77,7 +77,7 @@ static Void createBackupWithEncryptionKey(DatabaseAdminClient adminClient,
     Backup backup;
     try {
       System.out.println("Waiting for operation to complete...");
-      backup = operation.get(1200, TimeUnit.SECONDS);
+      backup = operation.get(3600, TimeUnit.SECONDS);
     } catch (ExecutionException e) {
       // If the operation failed during execution, expose the cause.
       throw SpannerExceptionFactory.asSpannerException(e.getCause());