Add Microsoft Java 11.0.15

11.0.15 is LTS version. It's important to have it in the list.

Fix https://github.com/actions/setup-java/issues/329

src/distributions/microsoft/installer.ts

@@ -93,6 +93,9 @@ export class MicrosoftDistributions extends JavaBase {
       jdkVersions.push({
         version: [11, 0, 13, 8, 1]
       });
+      jdkVersions.push({
+        version: [11, 0, 15]
+      });
     }
 
     return jdkVersions;