chore: Update config files to 1.1.21

Author: github-actions[bot]

docs/Writerside/v.list

@@ -2,5 +2,5 @@
 <!DOCTYPE vars SYSTEM "https://resources.jetbrains.com/writerside/1.0/vars.dtd">
 <vars>
     <var name="product" value="Writerside"/>
-    <var name="kotlinmailer_version" value="1.1.20"/>
+    <var name="kotlinmailer_version" value="1.1.21"/>
 </vars>

docs/Writerside/writerside.cfg

@@ -5,5 +5,5 @@
     <topics dir="topics" web-path="topics"/>
     <images dir="images" web-path="images"/>
     <snippets dir="snippets"/>
-    <instance src="default.tree" web-path="https://bierdav.github.io/Kotlinmailer/" version="v1.1.20"/>
+    <instance src="default.tree" web-path="https://bierdav.github.io/Kotlinmailer/" version="v1.1.21"/>
 </ihp>

gradle.properties

@@ -1,6 +1,6 @@
 name=Kotlinmailer
 group=at.quickme.kotlinmailer
 description=A simple coroutine based Kotlin Email API for client projects
-version=1.1.20
+version=1.1.21
 
 kotlin.code.style=official