Fix version.

Author: SebastianStehle

.github/workflows/dev.yml

@@ -66,7 +66,7 @@ jobs:
         if: github.event_name != 'pull_request'
         uses: kohlerdominik/[email protected]
         with:
-          image: mcr.microsoft.com/dotnet/sdk:7.0
+          image: mcr.microsoft.com/dotnet/sdk:8.0
           environment: |
             MAILCATCHER__HOST__SMTP=mailcatcher
             MESSAGEBIRD__ACCESSKEY=${{ secrets.MESSAGEBIRD__ACCESSKEY }}

.github/workflows/release.yml

@@ -59,7 +59,7 @@ jobs:
       - name: Test - RUN on GooglePubSub
         uses: kohlerdominik/[email protected]
         with:
-          image: mcr.microsoft.com/dotnet/sdk:7.0
+          image: mcr.microsoft.com/dotnet/sdk:8.0
           environment: |
             MAILCATCHER__HOST__SMTP=mailcatcher
             MESSAGEBIRD__ACCESSKEY=${{ secrets.MESSAGEBIRD__ACCESSKEY }}