Merge pull request #734 from aws-powertools/fix-apidocs-build

chore: Update api docs build to dotnet 8

Author: hjgraca

.github/workflows/docs.yml

@@ -54,10 +54,10 @@ jobs:
     environment: Docs
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
-      - name: Setup .NET 6.0
+      - name: Setup .NET 8.0
         uses: actions/setup-dotnet@87b7050bc53ea08284295505d98d2aa94301e852 # 4.2.0
         with:
-          dotnet-version: 6.0.405
+          dotnet-version: '8.x'
 
       - name: Build Api Docs
         run: |