chore: bump the snapcore/action-build action version (#505)

It [seems like there's only
1.3.0](https://github.com/snapcore/action-build/tags) available now,
although I'm not sure what the story is behind that. This blocks other
PRs from merging.

In any case, it seems reasonable to bump this to the latest available
1.x version. I couldn't find a changelog or release notes, but the
commits seem straightforward and unlikely to cause issues, and it is a
Canonical project.

.github/workflows/snap.yml

@@ -40,7 +40,7 @@ jobs:
 
       - name: Build ${{ env.SNAP_NAME }} Snap
         id: build-snap
-        uses: snapcore/action-build@v1.1.3
+        uses: snapcore/action-build@v1.3.0
 
       - uses: actions/upload-artifact@v3
         if: failure()
@@ -90,7 +90,7 @@ jobs:
 
       - name: Build ${{ env.SNAP_NAME }} Snap for ${{ matrix.arch }}
         id: build-snap
-        uses: snapcore/action-build@v1.1.3
+        uses: snapcore/action-build@v1.3.0
         with:
           snapcraft-args: remote-build --build-for=${{ matrix.arch }} --launchpad-accept-public-upload