Don't ignore resolved platform information

[kou]

This is a follow-up change of #7522.

What was the end-user problem that led to this PR?

The problem was installing wrong platform gem even when resolver resolves the correct platform gem.

See also:

• https://github.com/rubygems/bundler/pull/7522#issuecomment-574628275
• https://github.com/rubygems/bundler/pull/7522#issuecomment-574882536

What was your diagnosis of the problem?

My diagnosis was Bundler::LazySpecification#__materialize__ doesn't care about the resolved platform information.

What is your fix for the problem, implemented in this PR?

My fix cares about the resolved platform information.

Why did you choose this fix out of the possible options?

I chose this fix because we should respect the resolved platform information to install correct gem.

[deivid-rodriguez]

@bundlerbot merge

[ghost]

Build succeeded

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• windows (2.4.x)
• windows (2.5.x)
• windows (2.6.x)