chore: try to fix flipt provider test

Signed-off-by: Mark Phelps <[email protected]>

Author: markphelps

Diff for: providers/flipt/src/test/java/dev/openfeature/contrib/providers/flipt/FliptProviderTest.java

@@ -57,7 +57,7 @@ class FliptProviderTest {
 
     @BeforeAll
     void setUp(WireMockRuntimeInfo wmRuntimeInfo) {
-        apiUrl = "http://localhost:" + wmRuntimeInfo.getHttpPort(); 
+        apiUrl = "http://localhost:" + wmRuntimeInfo.getHttpPort();
         fliptProvider = buildFliptProvider();
         OpenFeatureAPI.getInstance().setProviderAndWait("sync", fliptProvider);
         client = OpenFeatureAPI.getInstance().getClient("sync");
@@ -76,7 +76,7 @@ private void mockFliptAPI(String url, String resourceName, String flagKey) {
                         .willReturn(
                                 aResponse()
                                         .withStatus(200)
-                                        .withHeader("Content-Type", "application/json")
+                                        .withHeader("Content-Type", "application/json; charset=UTF-8")
                                         .withBody(readResourceFileContent(resourceName))));
     }