Provide protoc-gen-mypy with LICENSE

contrib/python/mypy-protobuf/bin/protoc-gen-mypy/bin/ya.make

@@ -1,5 +1,7 @@
 PY3_PROGRAM_BIN(protoc-gen-mypy)
 
+LICENSE(Apache-2.0)
+
 PEERDIR(
     contrib/python/mypy-protobuf
 )

contrib/python/mypy-protobuf/bin/protoc-gen-mypy/ya.make

@@ -1,9 +1,9 @@
 IF (USE_PREBUILT_TOOLS)
-    INCLUDE(${ARCADIA_ROOT}/build/prebuilt/contrib/python/mypy-protobuf/bin/protoc-gen-mypy/ya.make.prebuilt)
+    INCLUDE(ya.make.prebuilt)
 ENDIF()
 
 IF (NOT PREBUILT)
-    INCLUDE(${ARCADIA_ROOT}/contrib/python/mypy-protobuf/bin/protoc-gen-mypy/bin/ya.make)
+    INCLUDE(bin/ya.make)
 ENDIF()
 
 RECURSE(