Update dependency com.willowtreeapps.assertk:assertk to v0.26.1

Author: renovate[bot]

settings.gradle.kts

@@ -18,7 +18,7 @@ dependencyResolutionManagement {
         val kotlin = "1.6.21"
         val kotlinxCoroutines = "1.6.4"
         val junit5 = "5.9.1"
-        val assertk = "0.25"
+        val assertk = "0.26.1"
         val androidGradlePlugin = "7.2.2"
         val dotenv = "2.0.0"
         val ktlint = "10.3.0"