Bump version code + number

Author: shorthouse

app/build.gradle.kts

@@ -17,8 +17,8 @@ android {
         applicationId = "dev.shorthouse.coinwatch"
         minSdk = 26
         targetSdk = 34
-        versionCode = 20
-        versionName = "1.2.5.1"
+        versionCode = 21
+        versionName = "1.2.6"
         ndk {
             debugSymbolLevel = "FULL"
         }