ci: Use --no-build-isolation to instal cgat

As [suggested](cgat-developers/cgat-apps#134 (comment)) attempting to install
dependencies (and in one instance `IsoSLAM` itself) with the `--no-build-isolation` flag in the hope that NumPy is
correctly detected by `cgat` when it is built and installed.

.github/workflows/sphinx_docs_to_gh_pages.yaml

@@ -24,7 +24,7 @@ jobs:
           python-version: 3.11
       - name: Installing the Documentation requirements
         run: |
-          pip3 install .[docs]
+          pip3 install --no-build-isolation .[docs]
       - name: Running Sphinx to gh-pages Action
         # Uncomment if only tagged releases are to have documentation built
         # if: startsWith(github.ref, 'refs/tags')

.github/workflows/tests.yaml

@@ -42,8 +42,8 @@ jobs:
           virtualenv --upgrade-embed-wheels
           pip install numpy
           pip show numpy
-          pip install cgatcore
-          pip install cgat
+          pip install --no-build-isolation cgatcore
+          pip install --no-build-isolation cgat
           pip install -e .[tests]
       - name: Test with pytest
         run: |