Add stanalone setup channel ID method for multiple channel ID use cases

[EagleVee]

PR Title

🔄 Type of change:

• ✨Feature/chore
• ♻️ Refactor
• 🔧 Bugfixes

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✏️ Description:

When using @xmartlabs/react-native-line on my project, my client requires that there are separate LINE channels for their separate corporations. So after some time digging in the source code, I found a way to use dynamic channel ID by export the LoginManager.setup method to React Native. I thought that this might be a good feature for the SDK so I created this PR. The coding might be not perfect since this is the first time I try to code on Kotlin and Swift, so recommendations are very appreciated!

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🎥 Screen record:

Add a screen record of the execution of your functionality. This way the reviewer can better understand what has been added.

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📌 Notes:

• Need a code review for the convention I used

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✔️Tasks:

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⚠️ Warnings:

• If the login method gets called before the configure method, the app will crash

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