fix: install elementary without [vertica] extra to prevent dbt-core downgrade (#966)

The 'Install Elementary' step was using pip install './elementary[vertica]'
which re-resolved dbt-vertica's dependencies, causing dbt-core to be
downgraded to ~1.7.3. The older dbt-core is incompatible with newer
protobuf (MessageToJson() missing 'including_default_value_fields' arg),
breaking the subsequent 'Install dependencies' step (dbt deps).

Since dbt-vertica is already installed with --no-deps in the prior step,
we install elementary without the [vertica] extra to preserve the
correct dbt-core version.

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: Itamar Hartstein <haritamar@gmail.com>

Author: devin-ai-integration[bot]

.github/workflows/test-warehouse.yml

@@ -183,7 +183,15 @@ jobs:
           curl -fsSL https://public.cdn.getdbt.com/fs/install/install.sh | sh -s --
 
       - name: Install Elementary
-        run: pip install "./elementary[${{ (inputs.warehouse-type == 'databricks_catalog' && 'databricks') || inputs.warehouse-type }}]"
+        run: |
+          # For Vertica, dbt-vertica is already installed with --no-deps above;
+          # using ".[vertica]" would re-resolve dbt-vertica's deps and downgrade
+          # dbt-core to ~=1.8.  Install elementary without the adapter extra.
+          if [ "${{ inputs.warehouse-type }}" = "vertica" ]; then
+            pip install "./elementary"
+          else
+            pip install "./elementary[${{ (inputs.warehouse-type == 'databricks_catalog' && 'databricks') || inputs.warehouse-type }}]"
+          fi
 
       - name: Write dbt profiles
         env: