Use default arch in CI (#144)

Author: JoshuaLampert

.github/workflows/CI.yml

@@ -30,7 +30,7 @@ concurrency:
 jobs:
   test:
     if: "!contains(github.event.head_commit.message, 'skip ci')"
-    name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ github.event_name }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -41,14 +41,11 @@ jobs:
           - ubuntu-latest
           - macos-latest
           - windows-latest
-        arch:
-          - x64
     steps:
       - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v2
         with:
           version: ${{ matrix.version }}
-          arch: ${{ matrix.arch }}
       - run: julia -e 'using InteractiveUtils; versioninfo(verbose=true)'
       - uses: julia-actions/cache@v2
       - uses: julia-actions/julia-buildpkg@v1
@@ -64,7 +61,7 @@ jobs:
       - uses: coverallsapp/github-action@v2
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
-          flag-name: run-${{ matrix.os }}-${{ matrix.version }}-${{ matrix.arch }}-${{ github.run_id }}
+          flag-name: run-${{ join(matrix.*, '-') }}
           parallel: true
           path-to-lcov: ./lcov.info
 

.github/workflows/Downgrade.yml

@@ -20,9 +20,9 @@ jobs:
   downgrade_test:
     if: "!contains(github.event.head_commit.message, 'skip ci')"
     # We could also include the Julia version as in
-    # name: ${{ matrix.trixi_test }} - ${{ matrix.os }} - Julia ${{ matrix.version }} - ${{ matrix.arch }} - ${{ github.event_name }}
+    # name: ${{ matrix.trixi_test }} - ${{ matrix.os }} - Julia ${{ matrix.version }} - ${{ github.event_name }}
     # to be more specific. However, that requires us updating the required CI tests whenever we update Julia.
-    name: Downgrade ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
+    name: Downgrade ${{ matrix.os }} - ${{ github.event_name }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -31,14 +31,11 @@ jobs:
           - '1.10'
         os:
           - ubuntu-latest
-        arch:
-          - x64
     steps:
       - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v2
         with:
           version: ${{ matrix.version }}
-          arch: ${{ matrix.arch }}
       - run: julia -e 'using InteractiveUtils; versioninfo(verbose=true)'
       - uses: julia-actions/cache@v2
       - uses: julia-actions/julia-downgrade-compat@v1