Fix a few typos found by codespell (#3543)

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## 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/uv-resolver/src/resolver/mod.rs

@@ -221,7 +221,7 @@ impl<'a, Context: BuildContext, InstalledPackages: InstalledPackagesProvider>
     /// reader of the resolution that knows to exclude distributions that can't
     /// be used in the current environment.
     ///
-    /// When a marker environment is provided, the reslver is in
+    /// When a marker environment is provided, the resolver is in
     /// "non-universal" mode, which corresponds to standard `pip` behavior that
     /// works only for a specific marker environment.
     #[allow(clippy::too_many_arguments)]
@@ -1376,7 +1376,7 @@ struct ResolverState {
     /// in this state. We also ultimately retrieve the final set of version
     /// assignments (to packages) from this state's "partial solution."
     pubgrub: State<UvDependencyProvider>,
-    /// The next package on which to run unit propgation.
+    /// The next package on which to run unit propagation.
     next: PubGrubPackage,
     /// The set of pinned versions we accrue throughout resolution.
     ///