ci: remove unnecessary quote marks for node versions

Co-authored-by: Michaël De Boey <[email protected]>

Author: Belco90

.github/workflows/pipeline.yml

@@ -53,7 +53,7 @@ jobs:
 
     strategy:
       matrix:
-        node: [ '10.22.1', '10', '12', '14' ]
+        node: [10.12, 10, 12.0, 12, 14, 15]
         eslint: [ '7.5', '7', ]
 
     steps: