Merge pull request grpc#22013 from voidzcy/release/update_interop_matrix_for_java_release

Update interop matrix for java release

Author: ericgribkoff

tools/interop_matrix/client_matrix.py

@@ -215,7 +215,8 @@ def __init__(self, patch=[], runtimes=[], testcases_file=None):
             ('v1.23.0', ReleaseInfo()),
             ('v1.24.0', ReleaseInfo()),
             ('v1.25.0', ReleaseInfo()),
-            ('v1.26.0', ReleaseInfo()),
+            ('v1.26.1', ReleaseInfo()),
+            ('v1.27.1', ReleaseInfo()),
         ]),
     'python':
         OrderedDict([