remove bids-validator pin

Author: sappelhoff

.github/workflows/unit_tests.yml

@@ -206,9 +206,8 @@ jobs:
 
     - name: Install BIDS validator (stable)
       if: matrix.bids-validator-version == 'validator-stable'
-      # XXX: Remove pin once this is solved: https://github.com/bids-standard/bids-validator/issues/2124
       run: |
-        npm install -g bids-validator@1.14.10
+        npm install -g bids-validator
 
     - name: Download BIDS validator (main)
       if: matrix.bids-validator-version == 'validator-main'