Update Gradle and ktlint (#105)

Author: igorwojda

.editorconfig

@@ -0,0 +1,2 @@
+[*.{kt,kts}]
+ktlint_custom-rule-set_filename = disabled

.github/workflows/run-checks.yml

@@ -32,13 +32,13 @@ jobs:
       - name: Verify project consistency
         run: cd .test && ./gradlew test
 
-      - name: ktlint check (test project)
-        run: cd .test && ./gradlew ktlintCheck
+      - name: spotless check (test project)
+        run: cd .test && ./gradlew spotlessCheck
 
-      - name: ktlint check (root project)
-        run: ./gradlew ktlintCheck
+      - name: spotless check (root project)
+        run: ./gradlew spotlessCheck
 
-      - name: Generate solutions tests
+      - name: Generate tests for every solution
         run: cd .test && ./gradlew generateTests
 
       - name: Navigate to root project