use snapshot of tla2b for testing

build.gradle

@@ -37,7 +37,7 @@ dependencies {
 	implementation(group: 'de.hhu.stups', name: 'ltlparser', version: parser_version)
 
 	testImplementation(group: 'junit', name: 'junit', version: '4.13.2')
-	testImplementation(group: 'de.hhu.stups', name: 'tla2bAST', version: '1.3.0')
+	testImplementation(group: 'de.hhu.stups', name: 'tla2bAST', version: '1.3.1-SNAPSHOT')
 }
 
 java {