Dependency resolution error

[RitchieP]

The following error showed up when trying to build my application with the package.

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:checkDebugDuplicateClasses'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.CheckDuplicatesRunnable
   > Duplicate class kotlin.collections.jdk8.CollectionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.internal.jdk8.JDK8PlatformImplementations found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.internal.jdk8.JDK8PlatformImplementations$ReflectSdkVersion found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.jvm.jdk8.JvmRepeatableKt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.jvm.optionals.OptionalsKt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.random.jdk8.PlatformThreadLocalRandom found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$1 found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$2 found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$3 found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$4 found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.text.jdk8.RegexExtensionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.time.jdk8.DurationConversionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.10 (org.jetbrains.kotlin:kotlin-stdlib:1.8.10) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)

     Go to the documentation to learn how to <a href="d.android.com/r/tools/classpath-sync-errors">Fix dependency resolution errors</a>.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

I noticed this issue was also briefly mentioned in #97 , but I think we may need to highlight this in the README to configure the kotlin version.

[jovazcode]

Same issue for me, with flutter_email_sender: 6.0.3

[√] Flutter (Channel stable, 3.22.1, on Microsoft Windows [Version 10.0.22631.3737], locale es-ES)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 32.0.0)
[√] Chrome - develop for the web
[√] Android Studio (version 2021.2)

Actually found that the issue appears since flutter_email_sender: 6.0.0 (previous one 5.2.0 is okay regarding this issue)