Bump vmactions/openbsd-vm from 1.1.8 to 1.2.0

Bumps [vmactions/openbsd-vm](https://github.com/vmactions/openbsd-vm) from 1.1.8 to 1.2.0.
- [Release notes](https://github.com/vmactions/openbsd-vm/releases)
- [Commits](https://github.com/vmactions/openbsd-vm/compare/v1.1.8...v1.2.0)

---
updated-dependencies:
- dependency-name: vmactions/openbsd-vm
  dependency-version: 1.2.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/build.yml

@@ -758,7 +758,7 @@ jobs:
         submodules: recursive
     - name: Build OpenBSD
       id: build-openbsd
-      uses: vmactions/openbsd-vm@v1.1.8
+      uses: vmactions/openbsd-vm@v1.2.0
       with:
         usesh: true
         mem: 4096