ci: escape backticked in bash.

Author: owtotwo

.github/workflows/semver-checks.yml

@@ -61,8 +61,8 @@ jobs:
       - name: note the solution for the failure of cargo-semver-checks
         if: ${{ contains(steps.semverchecks.outcome, 'failure') }}
         run: |
-          echo "::error::cargo-semver-checks failed, please add the hint comment to the `package.version` line in Cargo.toml file."
-          echo "::error::The version hint line should be like: `version = "0.0.0" # hint: <new_version>`"
+          echo "::error::cargo-semver-checks failed, please add the hint comment to the \`package.version\` line in Cargo.toml file."
+          echo "::error::The version hint line should be like: \`version = "0.0.0" # hint: <new_version>\`"
           echo "::error::Or you don't want to update the version, please check your code and find why cargo-semver-checks failed."
           exit 1
     #   - name: Create a PR for version update reminder