Update checkstyle-idea.properties

Author: james-baker-aera

src/main/resources/checkstyle-idea.properties

@@ -4,7 +4,7 @@ checkstyle.versions.supported = \
     9.0.1, 9.1, 9.2.1, 9.3, \
     10.0, 10.1, 10.2, 10.3.4, 10.4, 10.5.0, 10.6.0, 10.7.0, 10.8.1, 10.9.3, \
     10.10.0, 10.12.7, 10.13.0, 10.14.2, 10.15.0, 10.16.0, 10.17.0, 10.18.2, 10.19.0, \
-    10.20.2, 10.21.3, 10.22.0, 10.23.0, 10.24.0, 10.25.1
+    10.20.2, 10.21.3, 10.22.0, 10.23.0, 10.24.0, 10.25.1, 10.26.0
 
 # The "base version" must be one of the versions listed above. The sources are compiled against this version, so it is
 # the dependency shown in the IDE and the runtime used when unit tests are run from the IDE or via 'runCsaccessTests'.