Fix bazel.mk for Make v4.4.

As of version 4.4, Make will ignore phony build targets in include statements,
so we need to make a non-phony version of bazel-server that can be included.

See commit 0c2fc00544b89314643561dcb6d78f35eb98da68.

PiperOrigin-RevId: 689878525

tools/bazel.mk

@@ -39,7 +39,7 @@
 ##   To opt out of these wrappers, set DOCKER_BUILD=false.
 DOCKER_BUILD := true
 ifeq ($(DOCKER_BUILD),true)
--include bazel-server
+-include bazel-server-inc
 endif
 
 # See base Makefile.
@@ -256,6 +256,10 @@ bazel-server:
 endif
 .PHONY: bazel-server
 
+# As of version 4.4, Make will ignore phony targets in include statements, so
+# we make a non-phony version of bazel-server that can be included.
+bazel-server-inc: bazel-server
+
 # build_paths extracts the built binary from the bazel stderr output.
 #
 # The last line is used to prevent terminal shenanigans.