Update OkHttp to latest version

app/autodiscovery/src/main/java/com/fsck/k9/autodiscovery/thunderbird/ThunderbirdAutoconfigFetcher.kt

@@ -15,7 +15,7 @@ class ThunderbirdAutoconfigFetcher(private val okHttpClient: OkHttpClient) {
         val response = okHttpClient.newCall(request).execute()
 
         return if (response.isSuccessful) {
-            response.body()?.byteStream()
+            response.body?.byteStream()
         } else {
             null
         }

build.gradle

@@ -25,9 +25,7 @@ buildscript {
                 'koin': '0.9.1',
                 'commonsIo': '2.4',
                 'mime4j': '0.8.1',
-
-                // Note: Only use 3.12.x versions until we raise minSdkVersion to 21
-                'okhttp': '3.12.1',
+                'okhttp': '4.2.1',
 
                 'androidxTestRunner': '1.1.1',
                 'junit': '4.12',