freeze extras versions

Author: JJ11teen

setup.cfg

@@ -1,7 +1,7 @@
 [metadata]
 # replace with your username:
 name = cloud-mappings
-version = 0.7.3
+version = 0.7.4
 author = Lucas Sargent
 author_email = lucas.sargent@eliiza.com.au
 description = MutableMapping interfaces for common cloud storage providers
@@ -24,10 +24,10 @@ install_requires =
     zict>=2.0
 
 [options.extras_require]
-azure = azure-identity; azure-storage-blob
-aws = boto3
-gcp = google-cloud-storage
-tests = pytest
+azure = azure-identity==1.6.0; azure-storage-blob==12.8.1
+aws = boto3==1.17.73
+gcp = google-cloud-storage==1.38.0
+tests = pytest==6.2.4
 
 [options.packages.find]
 where = src