Auto merge of #10533 - willcrichton:fix-scrape-profile, r=epage

Auto merge of #10533 - willcrichton:fix-scrape-profile, r=epage

Fix how scrape-examples handles proc macros

### What does this PR try to resolve?

This PR fixes #10500.

Previously, the scrape-examples extension did some shenanigans in `build_unit_dependencies` in order to scrape `proc-macro` crates. But this code is useless since `proc-macro` crates cannot export functions, so we avoid this issue entirely by filtering proc-macro targets.

### How should we test and review this PR?

I added the test `scrape_examples_configure_profile` to ensure that the issue in #10500 is fixed.

r? `@ehuss`