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Speed up resolving requirements through `--use-first-matching-interpreter` Pex flag (#10442)

By default, when you pass a loose interpreter constraint to Pex like `>=3.6`, Pex will resolve for every interpreter discovered, e.g. 3.6 and 3.7 and 3.8. This results in the Pex being compatible with more interpreters at runtime.

However, the vast majority of our Pexes are never actually distributed to end-users so we don't care about compatibility - we only need one interpreter to work. The only time we need that compatibility is when using `awslambda` and `binary`, because those Pexes get materialized and distributed to the end-user.

Closes https://github.com/pantsbuild/pants/issues/10380 and https://github.com/pantsbuild/pants/issues/8685.

### Benchmark
Running `./pants --no-process-execution-use-local-cache --no-dynamic-ui --no-pantsd lint src/python/pants/util/strutil.py`, which will force building 4 Pex files, and output the starting and completion times.


|                   | Before (s) | After (s)   |
| :--------: | :----: | :---: |
| black.pex  |     9   |   5  |
| flake8.pex  |   8   |   3   |
| isort.pex  |   6   |   3  |
| docformatter.pex  |      4      |   3     |
| total (combined) | 27 | 18 |
| total (wall time)  | 9  | 5

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