Fix flake8 error in update_versions_html.py (pytorch#379)

Summary:
Seeing this unrelated error in pytorch#369: https://circleci.com/gh/pytorch/captum/6777?utm_campaign=vcs-integration-link&utm_medium=referral&utm_source=github-build-link.
Pull Request resolved: pytorch#379

Reviewed By: bilalsal

Differential Revision: D21514229

Pulled By: edward-io

fbshipit-source-id: 6a8f89807b7a9b930fcbfa2d3fe4332d91e3e5a8

scripts/update_versions_html.py

@@ -35,8 +35,8 @@ def prepend_url(a_tag, base_url, version):
 
         # nav
         nav_links = soup.find("nav").findAll("a")
-        for l in nav_links:
-            l.attrs["href"] = prepend_url(l, base_url, v)
+        for link in nav_links:
+            link.attrs["href"] = prepend_url(link, base_url, v)
 
         # version link
         t = soup.find("h2", {"class": "headerTitleWithLogo"}).find_next("a")