Bump org.jetbrains.kotlin:kotlin-stdlib in /docs/demos/common (#4060)

Bumps [org.jetbrains.kotlin:kotlin-stdlib](https://github.com/JetBrains/kotlin) from 1.3.72 to 1.6.0.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v1.6.0/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.3.72...v1.6.0)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-stdlib
  dependency-version: 1.6.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docs/demos/common/pom.xml

@@ -76,7 +76,7 @@
                 </file>
             </activation>
             <properties>
-                <kotlin.version>1.3.72</kotlin.version>
+                <kotlin.version>1.6.0</kotlin.version>
                 <kotlin.compiler.incremental>true</kotlin.compiler.incremental>
             </properties>
             <dependencies>