rename plugin name. (#50)

rename plugin name. Name should not contain such words as Plugin, IntelliJ, JetBrains.

Signed-off-by: he1pa <18012015693@163.com>

Author: He1pa

gradle.properties

@@ -1,7 +1,7 @@
 # IntelliJ Platform Artifacts Repositories -> https://plugins.jetbrains.com/docs/intellij/intellij-artifacts.html
 
 pluginGroup = io.kusionstack.kcl
-pluginName = intellij-kcl
+pluginName = kcl
 pluginRepositoryUrl = https://github.com/KusionStack/intellij-kcl
 # SemVer format -> https://semver.org
 pluginVersion = 0.4.0