test: mark http2 tests as flaky on 10.x

These tests are already marked as flaky on 12.x and master.

PR-URL: #31887
Reviewed-By: Beth Griggs <Bethany.Griggs@uk.ibm.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>

Author: AshCripps

test/parallel/parallel.status

@@ -11,6 +11,14 @@ test-net-connect-options-port: PASS,FLAKY
 test-trace-events-api-worker-disabled: PASS,FLAKY
 
 [$system==win32]
+# https://github.com/nodejs/node/issues/20750
+test-http2-client-upload: PASS,FLAKY
+# https://github.com/nodejs/node/issues/20750
+test-http2-client-upload-reject: PASS,FLAKY
+# https://github.com/nodejs/node/issues/30847
+test-http2-compat-client-upload-reject: PASS,FLAKY
+# https://github.com/nodejs/node/issues/30845
+test-http2-multistream-destroy-on-read-tls: PASS,FLAKY
 test-http2-pipe: PASS,FLAKY
 test-worker-syntax-error: PASS,FLAKY
 test-worker-syntax-error-file: PASS,FLAKY