Bump compileSdkVersion to fix semlette#55

Signed-off-by: Harry Chen <i@harrychen.xyz>

Author: Harry-Chen

android/build.gradle

@@ -1,7 +1,7 @@
 group 'im.nfc.flutter_nfc_kit'
 
 buildscript {
-    ext.kotlin_version = '1.6.0'
+    ext.kotlin_version = '1.6.21'
     repositories {
         google()
         mavenCentral()
@@ -24,7 +24,7 @@ apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
 
 android {
-    compileSdkVersion 29
+    compileSdkVersion 31
 
     sourceSets {
         main.java.srcDirs += 'src/main/kotlin'

example/android/app/build.gradle

@@ -40,6 +40,7 @@ android {
         applicationId "im.nfc.flutter_nfc_kit_example"
         minSdkVersion 19
         targetSdkVersion 31
+        compileSdkVersion 31
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

example/android/build.gradle

@@ -1,5 +1,5 @@
 buildscript {
-    ext.kotlin_version = '1.6.0'
+    ext.kotlin_version = '1.6.21'
     repositories {
         google()
         mavenCentral()