fix(ci): add databento to CI dependencies for test and type-check

The test job runs tests that import DatabentoHistoricalPriceSource,
and type-check analyzes app/services/backtesting/databento_source.py.
Both need the databento package installed.

.forgejo/workflows/deploy.yaml

@@ -44,7 +44,7 @@ jobs:
           set -x
           python -m pip install --upgrade pip
           pip install pytest pytest-asyncio httpx
-          pip install nicegui fastapi uvicorn yfinance polars pandas pydantic pyyaml
+          pip install nicegui fastapi uvicorn yfinance polars pandas pydantic pyyaml databento
           pip list
       - name: Run tests
         run: |
@@ -71,7 +71,7 @@ jobs:
           set -x
           python -m pip install --upgrade pip
           pip install mypy
-          pip install nicegui fastapi uvicorn yfinance polars pandas pydantic pyyaml
+          pip install nicegui fastapi uvicorn yfinance polars pandas pydantic pyyaml databento
           pip list
       - name: Show working directory
         run: pwd && ls -la