🍒applets/kicker: avoid calling reload() recursively

KSycoca::ensureCacheValid might emit databaseChanged signal again, which will cause a crash

SENTRY: PLASMA-WORKSPACE-5HC SENTRY: PLASMA-WORKSPACE-6P5 SENTRY: PLASMA-WORKSPACE-2KD BUG: 482887

(cherry picked from commit 2942dcf0)