external repos: fix typo confusing workspace_file_content and build_file_content

Fixes #5838

Change-Id: Ic5f730f97b43682b1efc537a02c861d49d3606cc
PiperOrigin-RevId: 208044984
diff --git a/tools/build_defs/repo/utils.bzl b/tools/build_defs/repo/utils.bzl
index e23556c..8a1ecaa 100644
--- a/tools/build_defs/repo/utils.bzl
+++ b/tools/build_defs/repo/utils.bzl
@@ -29,8 +29,9 @@
 def workspace_and_buildfile(ctx):
     """Utility function for writing WORKSPACE and, if requested, a BUILD file.
 
-    It assumes the paramters name, build_file, and build_file_contents to be
-    present in ctx.attr, the latter two possibly with value None.
+    It assumes the parameters name, build_file, build_file_contents,
+    workspace_file, and workspace_file_content to be
+    present in ctx.attr, the latter four possibly with value None.
 
     Args:
       ctx: The repository context of the repository rule calling this utility
@@ -49,7 +50,7 @@
     elif ctx.attr.workspace_file_content:
         bash_exe = ctx.os.environ["BAZEL_SH"] if "BAZEL_SH" in ctx.os.environ else "bash"
         ctx.execute([bash_exe, "-c", "rm -f WORKSPACE"])
-        ctx.file("WORKSPACE", ctx.attr.build_file_content)
+        ctx.file("WORKSPACE", ctx.attr.workspace_file_content)
     else:
         ctx.file("WORKSPACE", "workspace(name = \"{name}\")\n".format(name = ctx.name))