[INTERNAL] use JDK 11

SeeSharpSoft · SeeSharpSoft · commit 26d2e91a4409 · 2020-10-08T20:26:36.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,6 +1,6 @@
 language: java
 jdk:
-  - openjdk9
+  - openjdk11
 
 env:
   - IDEA_VERSION=PC-2019.3.3 GRAMMAR_KIT_VERSION=2019.3
diff --git a/gradle.properties b/gradle.properties
@@ -3,5 +3,5 @@
 # https://www.jetbrains.com/intellij-repository/snapshots
 
 name='CSV Plugin'
-javaVersion=9
-javaTargetVersion=9
+javaVersion=11
+javaTargetVersion=11
