Add requirements.txt file to have specific urllib

urllib version updated to have specific version.

Issue-ID: NONRTRIC-952
Signed-off-by: aravind.est <aravindhan.a@est.tech>
Change-Id: Ibf4b137702c37216c5c92742fbf86de86c012c89
diff --git a/tox.ini b/tox.ini
new file mode 100755
index 0000000..60e2f2c
--- /dev/null
+++ b/tox.ini
@@ -0,0 +1,38 @@
+#  ============LICENSE_START===============================================
+#  Copyright (C) 2023 Nordix Foundation. All rights reserved.
+#  ========================================================================
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#  ============LICENSE_END=================================================
+#
+
+# documentation only
+[tox]
+minversion = 2.0
+envlist =
+    docs,
+    docs-linkcheck,
+skipsdist = true
+
+[testenv:docs]
+basepython = python3
+deps = -r{toxinidir}/docs/requirements-docs.txt
+
+commands =
+    sphinx-build -W -b html -n -d {envtmpdir}/docs/doctrees ./docs/ {toxinidir}/docs/_build/html
+    echo "Generated docs available in {toxinidir}/docs/_build/html"
+allowlist_externals = echo
+
+[testenv:docs-linkcheck]
+basepython = python3
+deps = -r{toxinidir}/docs/requirements-docs.txt
+commands = sphinx-build -W -b linkcheck -d {envtmpdir}/doctrees ./docs/ {toxinidir}/docs/_build/linkcheck