Warn when BytecodeVersionValidator is ran without limits

BytecodeVersionValidator should not be ran in informative mode in
automated tests, where alternative BytecodeVersionJarValidatorJP
should be used instead.  Therefore add a warning issued when
BytecodeVersionValidator is ran in informative mode, which is treated
by test automation as failure.

src/main/java/org/fedoraproject/javapackages/validator/validators/BytecodeVersionValidator.java

@@ -65,6 +65,7 @@ public Limits readLimits() {
     public void validate(RpmPackage rpm, Path jarPath, Map<Path, Version> classVersions) {
         var limits = readLimits();
         if (limits == null) {
+            warn("No limits were configured for " + getTestName() + ", the results will only be informative.");
             super.validate(rpm, jarPath, classVersions);
             return;
         }

src/test/java/org/fedoraproject/javapackages/validator/TestCommon.java

@@ -43,6 +43,10 @@ public static void assertInfo(Result result) {
         assertEquals(TestResult.info, result.getResult(), "expected result: INFO");
     }
 
+    public static void assertWarn(Result result) {
+        assertEquals(TestResult.warn, result.getResult(), "expected result: WARN");
+    }
+
     public static void assertFailOne(Result result) {
         assertEquals(TestResult.fail, result.getResult(), "expected result: FAIL");
         int count = 0;

src/test/java/org/fedoraproject/javapackages/validator/validators/BytecodeVersionValidatorTest.java

@@ -2,8 +2,8 @@
 
 import static org.fedoraproject.javapackages.validator.TestCommon.assertError;
 import static org.fedoraproject.javapackages.validator.TestCommon.assertFailOne;
-import static org.fedoraproject.javapackages.validator.TestCommon.assertInfo;
 import static org.fedoraproject.javapackages.validator.TestCommon.assertPass;
+import static org.fedoraproject.javapackages.validator.TestCommon.assertWarn;
 import static org.junit.jupiter.api.Assertions.fail;
 
 import java.nio.file.Path;
@@ -52,10 +52,11 @@ void assertMsg(String exp) {
     }
 
     @Test
-    void testInfo() throws Exception {
+    void testInformative() throws Exception {
         validator.validate(RPMS, null);
-        assertInfo(validator.build());
+        assertWarn(validator.build());
         assertMsg("module-info.class: bytecode version: 65.0");
+        assertMsg("No limits were configured for /java/bytecode-version, the results will only be informative");
     }
 
     @Test