Update action path to work on windows

Previously the path to the action script was `${{ github.action_path }}`
which uses the native path format. On Windows machines this ends up
passing paths with `\` to bash, which bash tries to interpret as escape
characters. "c:\a\b" would get be interpreted as "c:ab".

Now the path replaces all instances of `\` with `/` to work with bash on
Windows. This assumes that `\` would never be used on other github
runners.

Solution was copied from actions/runner#1066

action.yml

@@ -18,7 +18,7 @@ runs:
     - uses: actions/setup-go@v3
       with:
         go-version: ${{ inputs.go_version }}
-    - run: ${{ github.action_path }}/build_and_release.sh
+    - run: ${GITHUB_ACTION_PATH//\\//}/build_and_release.sh
       env:
         GITHUB_REPOSITORY: ${{ github.repository }}
         GITHUB_TOKEN: ${{ github.token }}