Update requirements.txt to not be so strict (#6)

requirements.txt

@@ -2,27 +2,6 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-build==0.10.0
-cachetools==5.3.0
-certifi==2023.5.7
-chardet==5.1.0
-charset-normalizer==3.1.0
-colorama==0.4.6
-distlib==0.3.6
-filelock==3.12.0
-hvac==1.1.0
-idna==3.4
-packaging==23.1
-pbr==5.11.1
-platformdirs==3.5.0
-pluggy==1.0.0
-pyhcl==0.4.4
-pyproject_api==1.5.1
-pyproject_hooks==1.0.0
-requests==2.30.0
-six==1.16.0
-tenacity==8.2.2
-tomli==2.0.1
-tox==4.5.1
-urllib3==2.0.2
-virtualenv==20.23.0
+hvac>=1.1.0
+pbr>=5.11.1
+tenacity>=8.2.2