fix: show warning when the platform's version in project's podfile will be replaced with another platform's version

[Fatme]

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What is the current behavior?

No warning is shown when platform's version in project's podfile is replaced with another platform's version

What is the new behavior?

Warning is shown when platform's version in project's podfile is replaced with another platform's version

Fixes/Implements/Closes #[Issue Number].

Rel to: #3604