build(deps-dev): bump com.diffplug.spotless:spotless-maven-plugin from 3.3.0 to 3.4.0 in /block-kit (#29)

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Author: dependabot[bot]

block-kit/pom.xml

@@ -22,7 +22,7 @@
       <plugin>
         <groupId>com.diffplug.spotless</groupId>
         <artifactId>spotless-maven-plugin</artifactId>
-        <version>3.3.0</version>
+        <version>3.4.0</version>
         <configuration>
           <formats>
             <format>