escript: drop support for the magic "erlang_test_runner" label

Summary: This is not necessary as of D62954867

Reviewed By: IanChilds

Differential Revision: D65273613

fbshipit-source-id: 874b3d92eb9408cd4ef63771bb9d70c5d84931c8

prelude/erlang/erlang_escript.bzl

@@ -99,10 +99,6 @@ def _bundled_escript_impl(ctx: AnalysisContext, dependencies: ErlAppDependencies
                 fail("multiple artifacts defined for path %s", (artifact.short_path))
             artifacts[artifact.short_path] = artifact
 
-    # magic tag to make vendored json available to the test binary
-    if "erlang_test_runner" in ctx.attrs.labels:
-        artifacts["utility_modules/ebin"] = toolchain.utility_modules
-
     escript_name = _escript_name(ctx)
     output = ctx.actions.declare_output(escript_name)