fix: add installation of system libs for pymssql in CI workflow

Install `freetds-dev` (and build-essentials) so `pymssql` can compile against the FreeTDS headers.

Author: Lukas Alberto Belck

.github/workflows/main.yml

@@ -79,6 +79,10 @@ jobs:
               uses: actions/setup-python@v4
               with:
                   python-version: ${{ matrix.python-version }}
+            - name: Install system libs for pymssql
+              run: |
+                    sudo apt-get update
+                    sudo apt-get install --yes build-essential freetds-dev freetds-bin
             - name: Install Project
               run: |
                   python -m pip install --upgrade pip