GUACAMOLE-1859: Update to Kotlin 1.9.21.

doc/licenses/kotlin-1.9.10/dep-coordinates.txt

@@ -1,5 +0,0 @@
-org.jetbrains.kotlin:kotlin-reflect:jar:1.9.10
-org.jetbrains.kotlin:kotlin-stdlib:jar:1.9.10
-org.jetbrains.kotlin:kotlin-stdlib-common:jar:1.9.10
-org.jetbrains.kotlin:kotlin-stdlib-jdk8:jar:1.9.10
-org.jetbrains.kotlin:kotlin-stdlib-jdk7:jar:1.9.10

doc/licenses/kotlin-1.9.21/README

@@ -1,7 +1,7 @@
 Kotlin (https://kotlinlang.org/)
 --------------------------------
 
-    Version: 1.9.10
+    Version: 1.9.21
     From: 'JetBrains s.r.o and respective authors and developers'
     License(s):
         Apache v2.0

doc/licenses/kotlin-1.9.21/dep-coordinates.txt

@@ -0,0 +1,5 @@
+org.jetbrains.kotlin:kotlin-reflect:jar:1.9.21
+org.jetbrains.kotlin:kotlin-stdlib:jar:1.9.21
+org.jetbrains.kotlin:kotlin-stdlib-common:jar:1.9.21
+org.jetbrains.kotlin:kotlin-stdlib-jdk8:jar:1.9.21
+org.jetbrains.kotlin:kotlin-stdlib-jdk7:jar:1.9.21

extensions/guacamole-vault/modules/guacamole-vault-ksm/pom.xml

@@ -38,7 +38,7 @@
     </parent>
 
     <properties>
-        <kotlin.version>1.9.10</kotlin.version>
+        <kotlin.version>1.9.21</kotlin.version>
     </properties>
 
     <dependencies>