Bump kotlinVersion from 1.4.30 to 1.4.31

Bumps `kotlinVersion` from 1.4.30 to 1.4.31.

Updates `kotlin-gradle-plugin` from 1.4.30 to 1.4.31
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v1.4.31/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.4.30...v1.4.31)

Updates `kotlin-stdlib-jdk8` from 1.4.30 to 1.4.31
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v1.4.31/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.4.30...v1.4.31)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

build.gradle

@@ -1,6 +1,6 @@
 buildscript {
     ext {
-        kotlinVersion = '1.4.30'
+        kotlinVersion = '1.4.31'
         moshiVersion = "1.9.2"
     }