Fix plugin references to moved :plugin-api

The plugin api moved into the gerrit-plugin-api package.
Change the reference created by gerrit_plugin() to match.

Change-Id: I390a22f512835847367ae2993a7a9bddf9d11b5c

tools/default.defs

@@ -162,7 +162,7 @@ def gerrit_plugin(
     srcs = srcs,
     resources = resources,
     deps = deps,
-    compile_deps = ['//:%s-lib' % type] + gwt_deps,
+    compile_deps = ['//gerrit-%s-api:lib' % type] + gwt_deps,
   )
   if gwt_module:
     prebuilt_jar(