bump python to 3.8 for docs action (#114)

* bump docs CI python to 3.8
* attempt to fix deploy on tag upload

Author: IAlibay

.github/workflows/deploy.yaml

@@ -4,6 +4,7 @@ on:
   push:
     branches:
       - master
+    tags:
   pull_request:
     branches:
       - master

.github/workflows/docs.yaml

@@ -25,7 +25,7 @@ jobs:
     - name: setup_miniconda
       uses: conda-incubator/setup-miniconda@v2
       with:
-        python-version: 3.7
+        python-version: 3.8
         auto-update-conda: true
         channel-priority: flexible
         channels: conda-forge