Changed workaround according to recommendation by Jetbrains.

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/JoinStatementsQuickFix.kt

@@ -56,14 +56,8 @@ class JoinStatementsQuickFix(private val separateLineLimit: Int) : AbstractCommo
     }
 
     private fun addLineBreak(project: Project, lastElementBeforeConcat: PsiElement) {
-        val newLineNode = try {
-            PsiParserFacade.getInstance(project).createWhiteSpaceFromText("\n\t")
-        } catch (ex: NoSuchMethodError) {
-            // scheduled for removal, but alternate version not even available in 2020.3.
-            // So keep it here until we run into a problem.
-            // Changing the min version from 2017.3 to 2021.x is a major thing.
-            PsiParserFacade.SERVICE.getInstance(project).createWhiteSpaceFromText("\n\t")
-        }
+        // was PsiParserFacade.getInstance(project).createWhiteSpaceFromText("\n\t"), changed due to breaking API changes
+        val newLineNode = project.getService(PsiParserFacade::class.java).createWhiteSpaceFromText("\n\t")
         lastElementBeforeConcat.addAfter(newLineNode, lastElementBeforeConcat.firstChild)
     }