Fix Link Checker (#127)

use `root-dir` with $pwd

Author: dvdvgt

.github/workflows/link-validator.yml

@@ -21,4 +21,4 @@ jobs:
         id: lychee
         uses: lycheeverse/lychee-action@v2
         with:
-          args: --base . --require-https --max-redirects 10 --suggest --verbose --accept '100..=103,200..=299,403' --exclude-path 'effekt/kiama' --exclude '^file://.*' './**/*.md'
+          args: --root-dir $(pwd) --require-https --max-redirects 10 --suggest --verbose --accept '100..=103,200..=299,403' --exclude-path 'effekt/kiama' --exclude '^file://.*' './**/*.md'