Pin urllib3 to older release to avoid issues related to Python being

compiled against old openssl version.

tox.ini

@@ -204,7 +204,10 @@ commands = python ./contrib/generate_provider_feature_matrix_table.py
 
 [testenv:scrape-and-publish-provider-prices]
 basepython: python3.8
-deps = requests
+# Needed to avoid urllib3 errors related to old openssl version
+# https://github.com/urllib3/urllib3/issues/2168
+deps = urllib3==1.26.6
+       requests
        jsonnet
        ijson
        tqdm
@@ -235,7 +238,10 @@ commands =
 
 [testenv:scrape-provider-prices]
 basepython: python3.8
-deps = requests
+# Needed to avoid urllib3 errors related to old openssl version
+# https://github.com/urllib3/urllib3/issues/2168
+deps = urllib3==1.26.6
+       requests
        jsonnet
        ijson
 passenv =
@@ -255,15 +261,21 @@ commands =
 
 [testenv:scrape-ec2-prices]
 basepython: python3.7
-deps = requests
+# Needed to avoid urllib3 errors related to old openssl version
+# https://github.com/urllib3/urllib3/issues/2168
+deps = urllib3==1.26.6
+       requests
        jsonnet
        ijson
        tqdm
 commands = python contrib/scrape-ec2-prices.py
 
 [testenv:scrape-ec2-sizes]
 basepython: python3.7
-deps = requests
+# Needed to avoid urllib3 errors related to old openssl version
+# https://github.com/urllib3/urllib3/issues/2168
+deps = urllib3==1.26.6
+       requests
        ijson
        tqdm
 commands =