keep gemstone 3.7.0 in the list as well

Author: Johan Brichau

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        smalltalk: [ Pharo64-12, Pharo64-11, Pharo64-10, Pharo64-9.0, Pharo64-8.0, Pharo64-7.0, GemStone64-3.7.1, GemStone64-3.6.8, GemStone64-3.5.8, Squeak64-5.3 ]
+        smalltalk: [ Pharo64-12, Pharo64-11, Pharo64-10, Pharo64-9.0, Pharo64-8.0, Pharo64-7.0, GemStone64-3.7.0, GemStone64-3.7.1, GemStone64-3.6.8, GemStone64-3.5.8, Squeak64-5.3 ]
         experimental: [ false ]
         include:
           - smalltalk: Pharo64-13