Bump logback-classic from 1.2.5 to 1.2.6

Bumps logback-classic from 1.2.5 to 1.2.6.

---
updated-dependencies:
- dependency-name: ch.qos.logback:logback-classic
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

uhabits-server/build.gradle.kts

@@ -35,7 +35,7 @@ application {
 dependencies {
     val ktorVersion = "1.6.4"
     val kotlinVersion = "1.5.31"
-    val logbackVersion = "1.2.5"
+    val logbackVersion = "1.2.6"
     implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion")
     implementation("io.ktor:ktor-server-netty:$ktorVersion")
     implementation("ch.qos.logback:logback-classic:$logbackVersion")