fix: podspec file indentation

[olessavluk]

Summary

After https://github.com/callstack/react-native-builder-bob/pull/358 identation become shifted which makes code hard to read and could lead to bugs. For example I was placing package dependencies inside if/else block, right after s.dependency "React-Core"

see

before	after

Test plan

Purely aesthetic changes, so nothing to break

[olessavluk]

cc @ykhateeb