Fixed error "You are applying Flutter’s app_plugin_loader Gradle plugin imperatively"

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Description

• Fixed this error while trying to compile for Android:

What went wrong:
A problem occurred evaluating script.
> You are applying Flutter’s app_plugin_loader Gradle plugin imperatively using the apply script method, which is not possible
Also: 
Migrate to applying Gradle plugins with the declarative plugins block

• Upgrade multiple libs
• Had to update the minimum iOS version

Preview

Fixed:

@rs-gpt-review Describe the changes in this PR. Recommend improvements (including code improvements), possible memory leaks, and best practices.