Bump julia-actions/julia-downgrade-compat from 1 to 2 (#57)

* Bump julia-actions/julia-downgrade-compat from 1 to 2

Bumps [julia-actions/julia-downgrade-compat](https://github.com/julia-actions/julia-downgrade-compat) from 1 to 2.
- [Release notes](https://github.com/julia-actions/julia-downgrade-compat/releases)
- [Commits](julia-actions/julia-downgrade-compat@v1...v2)

---
updated-dependencies:
- dependency-name: julia-actions/julia-downgrade-compat
  dependency-version: '2'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

* Run downgrade action with same version of Julia

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Seth Axen <seth@sethaxen.com>

Author: dependabot[bot]

.github/workflows/CI.yml

@@ -49,13 +49,15 @@ jobs:
         env:
           GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
       - uses: julia-actions/setup-julia@v2
+        id: setup-julia
         with:
           version: ${{ matrix.version }}
           arch: ${{ matrix.arch }}
       - uses: julia-actions/cache@v2
-      - uses: julia-actions/julia-downgrade-compat@v1
+      - uses: julia-actions/julia-downgrade-compat@v2
         with:
           skip: LinearAlgebra,Markdown,Printf,Random,Statistics,ArviZExampleData
+          julia_version: ${{ steps['setup-julia'].outputs.julia-version }}
         if: ${{ matrix.downgrade }}
         name: Downgrade dependencies to oldest supported versions
       - uses: julia-actions/julia-buildpkg@v1