Bump kotlin-stdlib from 1.6.10 to 1.6.21

Bumps [kotlin-stdlib](https://github.com/JetBrains/kotlin) from 1.6.10 to 1.6.21.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v1.6.21/ChangeLog.md)
- [Commits](https://github.com/JetBrains/kotlin/compare/v1.6.10...v1.6.21)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-stdlib
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

uhabits-core/build.gradle.kts

@@ -45,7 +45,7 @@ kotlin {
                 implementation(kotlin("stdlib-jdk8"))
                 compileOnly("com.google.dagger:dagger:2.41")
                 implementation("com.google.guava:guava:31.1-android")
-                implementation("org.jetbrains.kotlin:kotlin-stdlib:1.6.10")
+                implementation("org.jetbrains.kotlin:kotlin-stdlib:1.6.21")
                 implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core-jvm:1.6.0")
                 implementation("androidx.annotation:annotation:1.3.0")
                 implementation("com.google.code.findbugs:jsr305:3.0.2")