pin uv to 0.7.22 in the GitHub Action (#8585)

Due to rstudio/reticulate#1811 we need to pin uv to a 0.7 version until reticulate is fixed


### QA Notes
@:reticulate
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Author: jonvanausdeln

.github/actions/install-python/action.yml

@@ -18,8 +18,11 @@ runs:
       with:
         python-version: '3.12.6'
 
+    # Pinning UV due to https://github.com/rstudio/reticulate/issues/1811
     - name: Install uv
       uses: astral-sh/setup-uv@v5
+      with:
+        version: "0.7.22"
 
     - name: Install Python dependencies
       shell: bash