Fix: Pin urllib3 and fix license link

- Fix broken license link
- Pin urllib3 in the tox dependencies
- allowlist_externals for echo

Change-Id: Id13e0e2795394f66bef2ac9656e08e127cd7b290
Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
diff --git a/tox.ini b/tox.ini
index a2250a7..5fc51fe 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,7 +14,8 @@
     sphinxcontrib-httpdomain
     recommonmark
     lfdocs-conf
-
+    urllib3~=1.26.15
+allowlist_externals = echo
 commands =
     sphinx-build -W -b html -n -d {envtmpdir}/doctrees ./docs/ {toxinidir}/docs/_build/html
 
@@ -29,4 +30,5 @@
        sphinxcontrib-httpdomain
        recommonmark
        lfdocs-conf
+       urllib3~=1.26.15
 commands = sphinx-build -W -b linkcheck -d {envtmpdir}/doctrees ./docs/ {toxinidir}/docs/_build/linkcheck