CI: update the release workflow

Author: nosborn

.github/workflows/release.yml

@@ -26,9 +26,9 @@ jobs:
 
       - name: Check embedded version numbers
         run: |
-          version="$(grep -F "uses: ${GITHUB.REPOSITORY}@" README.md | cut -d@ -f2)"
+          version="$(grep -F "uses: ${GITHUB_REPOSITORY}@" README.md | cut -d@ -f2)"
           if [[ ${version} != "${GITHUB_REF_NAME}" ]]; then
-            line="$(grep -Fn "uses: ${GITHUB.REPOSITORY}@" README.md | cut -d: -f1)"
+            line="$(grep -Fn "uses: ${GITHUB_REPOSITORY}@" README.md | cut -d: -f1)"
             printf '::error file=README.md,line=%d::version does not match tag\n' "${line}"
             rc=1
           fi