Fix context leak in LocationProviderImpl.kt

[Chaoba]

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Fixes: < Link to related issues that will be fixed by this pull request, if they exist >

Pull request checklist:

• Briefly describe the changes in this PR.
• Include before/after visuals or gifs if this PR includes visual changes.
• Write tests for all new functionality. If tests were not written, please explain why.
• Optimize code for java consumption (@JvmOverloads, @file:JvmName, etc).
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Summary of changes

This pr uses WeakReference to wrap context instance to prevent context leak.

User impact (optional)

[kiryldz]

LGTM with a nit