Remove passing lists of args to genrule

This is required for this migration bazelbuild/bazel#5903

lib/apple_support.bzl

@@ -446,16 +446,6 @@ def _run_shell(
         actions = actions,
     )
 
-    # TODO(b/77637734) remove "workaround" once the bazel issue is resolved.
-    # Bazel doesn't always get the shell right for a single string `commands`;
-    # so work around that case by faking it as a list of strings that forces
-    # the shell correctly.
-    command = kwargs.get("command")
-    if command and types.is_string(command):
-        processed_args = dict(kwargs)
-        processed_args["command"] = ["/bin/sh", "-c", command]
-        kwargs = processed_args
-
     if not actions:
         actions = ctx.actions
 

rules/apple_genrule.bzl

@@ -80,7 +80,7 @@ def _apple_genrule_impl(ctx):
         inputs = resolved_srcs.to_list() + resolved_inputs,
         outputs = files_to_build.to_list(),
         env = ctx.configuration.default_shell_env,
-        command = argv,
+        command = " ".join(argv),
         progress_message = "%s %s" % (message, ctx.label),
         mnemonic = "Genrule",
         input_manifests = runfiles_manifests,

test/apple_support_test.bzl

@@ -172,10 +172,10 @@ def _apple_support_test_impl(ctx):
         ctx,
         outputs = [run_shell_output],
         tools = [test_tool],
-        command = ["/bin/bash", "-c", "{tool} {output}".format(
+        command = "{tool} {output}".format(
             output = run_shell_output.path,
             tool = test_tool.path,
-        )],
+        ),
     )
 
     test_files = [