ENH: Remove unnecessary docs/requirements.txt

.github/workflows/docs-build-pr.yml

@@ -40,7 +40,7 @@ jobs:
     - name: Install dependencies
       run: |
         pip install -U build hatch pip
-        pip install -r docs/requirements.txt
+        pip install .[doc]
         python -m hatch version | tail -n1
 
     - name: Build docs

.github/workflows/docs-build-update.yml

@@ -43,7 +43,7 @@ jobs:
     - name: Install dependencies
       run: |
         pip install -U build hatch pip
-        pip install -r docs/requirements.txt
+        pip install .[doc]
         python -m hatch version | tail -n1
 
     - name: Build docs