CI: Fix grammar and mark MacOS workflow as aarch64 not amd64

Looks like GitHub now uses aarch64 machines for MacOS workflows according
to this document:
https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#standard-github-hosted-runners-for-public-repositories

Signed-off-by: Mobin Aydinfar <mobin@mobintestserver.ir>

.github/workflows/regular_ci.yml

@@ -82,13 +82,13 @@ jobs:
       fail-fast: false # Upload src/igr-tests/*/output/* files in igr-tests
       matrix:
         include:
-          - arch: 'amd64'
+          - arch: 'aarch64'
 
     steps:
     - uses: actions/checkout@v4
     # on MacOS, g++ symlinked to clang++
     # We must verify that
-    - name: Verify g++ (it is g++ or clang++?)
+    - name: Verify g++ (is it g++ or clang++?)
       run: g++ --version
     - name: Print g++ architecture
       run: g++ -dumpmachine