Fix build warning: Unlimited fetch depth

SonarCloud is showing a warning that the shallow clone is hurting analysis.
I'll fix this by doing a deep clone.  There's nothing big here to hurt this,
so I bet the impact on build performance will be negligible.

Author: craigfowler

.github/workflows/dotnetCi.yml

@@ -43,6 +43,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
 
       # Install build dependencies