Travis: OSX tests are working again now,

Author: Abscissa

.travis.yml

@@ -346,32 +346,4 @@ matrix:
     # These are currently failing because mysql-native does not yet
     # support MySQL v8.0.4's new default authentication mechanism: caching_sha2_password
     # See issue #189: https://github.com/mysql-d/mysql-native/issues/189
-    - d: dmd-2.080.0
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: dmd-2.079.1
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: dmd-2.078.3
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: ldc-1.9.0
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: ldc-1.8.0
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: dmd-2.068.2
-      env: NO_VIBE=true
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
-
-    - d: ldc-0.17.0
-      env: NO_VIBE=true
-      os: osx
-      osx_image: xcode9.4 # use OSX 10.13
+    #TODO: Add test for OSX brew's latest available mysql server