Use more meaningful variable names in release workflow

A GitHub Actions workflow is used to automatically generate production builds of the project.

A separate build is generated for each of the target host types. This is done using a job matrix, which creates a
parallel run of the workflow job for each target. The matrix defines variables that provide the data that is specific to
each job.

The variable names used previously did not clearly communicate their nature:

- The variable for the task name was named "os"
- The variables for the build filename components used the term "artifact", which is ambiguous in this context where the
term is otherwise used to refer to the completely unrelated workflow artifacts

These variable names made it very difficult for anyone not intimately familiar with the workings of the workflow to
understand its code.

Author: per1234

.github/workflows/release-go-task.yml

@@ -65,7 +65,7 @@ jobs:
           path: ${{ env.DIST_DIR }}
 
   notarize-macos:
-    name: Notarize ${{ matrix.artifact.name }}
+    name: Notarize ${{ matrix.build.folder-suffix }}
     runs-on: macos-latest
     needs: create-release-artifacts
 
@@ -74,11 +74,11 @@ jobs:
 
     strategy:
       matrix:
-        artifact:
-          - name: darwin_amd64
-            path: "macOS_64bit.tar.gz"
-          - name: darwin_arm64
-            path: "macOS_ARM64.tar.gz"
+        build:
+          - folder-suffix: darwin_amd64
+            package-suffix: "macOS_64bit.tar.gz"
+          - folder-suffix: darwin_arm64
+            package-suffix: "macOS_ARM64.tar.gz"
 
     steps:
       - name: Checkout repository
@@ -124,7 +124,7 @@ jobs:
         run: |
           cat > "${{ env.GON_CONFIG_PATH }}" <<EOF
           # See: https://github.com/Bearer/gon#configuration-file
-          source = ["${{ env.DIST_DIR }}/${{ env.PROJECT_NAME }}_osx_${{ matrix.artifact.name }}/${{ env.PROJECT_NAME }}"]
+          source = ["${{ env.DIST_DIR }}/${{ env.PROJECT_NAME }}_osx_${{ matrix.build.folder-suffix }}/${{ env.PROJECT_NAME }}"]
           bundle_id = "cc.arduino.${{ env.PROJECT_NAME }}"
 
           sign {
@@ -154,10 +154,10 @@ jobs:
         run: |
           # GitHub's upload/download-artifact actions don't preserve file permissions,
           # so we need to add execution permission back until the action is made to do this.
-          chmod +x "${{ env.PROJECT_NAME }}_osx_${{ matrix.artifact.name }}/${{ env.PROJECT_NAME }}"
+          chmod +x "${{ env.PROJECT_NAME }}_osx_${{ matrix.build.folder-suffix }}/${{ env.PROJECT_NAME }}"
           TAG="${GITHUB_REF/refs\/tags\//}"
-          PACKAGE_FILENAME="${{ env.PROJECT_NAME }}_${TAG}_${{ matrix.artifact.path }}"
-          tar -czvf "$PACKAGE_FILENAME" "${{ env.PROJECT_NAME }}_osx_${{ matrix.artifact.name }}"
+          PACKAGE_FILENAME="${{ env.PROJECT_NAME }}_${TAG}_${{ matrix.build.package-suffix }}"
+          tar -czvf "$PACKAGE_FILENAME" "${{ env.PROJECT_NAME }}_osx_${{ matrix.build.folder-suffix }}"
           echo "PACKAGE_FILENAME=$PACKAGE_FILENAME" >> $GITHUB_ENV
 
       - name: Upload artifact