Fix a few typos found by codespell (#3543)

<!--
Thank you for contributing to uv! To help us out with reviewing, please
consider the following:

- Does this pull request include a summary of the change? (See below.)
- Does this pull request include a descriptive title?
- Does this pull request include references to any relevant issues?
-->

## Summary

Just fix typos.

While `alpha-numeric` is not really a misspelling:
- it is missing from mainstream curated dictionaries, all of them
suggest `alphanumeric`;
- it is less used than `alphanumeric` (more than ⨉10 less) according to
the Google [Ngram
Viewer](https://books.google.com/ngrams/graph?content=alpha-numeric%2Calphanumeric&year_start=1900&year_end=2019&corpus=en-2019);
- it is [missing from
SCOWL](http://app.aspell.net/lookup?dict=en_US-large;words=alpha-numeric).

## Test Plan

CI jobs.

crates/pep440-rs/src/version.rs

@@ -2098,7 +2098,7 @@ impl std::fmt::Display for VersionParseError {
                 write!(
                     f,
                     "found a `{precursor}` indicating the start of a local \
-                     component in a version, but did not find any alpha-numeric \
+                     component in a version, but did not find any alphanumeric \
                      ASCII segment following the `{precursor}`",
                 )
             }
@@ -2138,7 +2138,7 @@ pub(crate) enum ErrorKind {
     /// Occurs when an epoch version does not have a number after the `!`.
     NoLeadingReleaseNumber,
     /// Occurs when a `+` (or a `.` after the first local segment) is seen
-    /// (indicating a local component of a version), but no alpha-numeric ASCII
+    /// (indicating a local component of a version), but no alphanumeric ASCII
     /// string is found following it.
     LocalEmpty {
         /// Either a `+` or a `[-_.]` indicating what was found that demands a