Minor internal README enhancement for Markdown list in PEP440 (#13880)

- Define all list elements using `-`: it used to be a mix of `*` and
`-`. `-` is what Prettier linter formats it to by default.
- Removed unnecessary blank line between 2 list elements. Other elements
were stitched together without blank lines in between.
- Only the first list element started in sentence case (capital letter
first) - I made all start like so.

crates/uv-pep440/Readme.md

@@ -26,20 +26,19 @@ PEP 440 has a lot of unintuitive features, including:
 
 - An epoch that you can prefix the version with, e.g., `1!1.2.3`. Lower epoch always means lower
   version (`1.0 <=2!0.1`)
-
-* post versions, which can be attached to both stable releases and pre-releases
-* dev versions, which can be attached to sbpth table releases and pre-releases. When attached to a
+- Post versions, which can be attached to both stable releases and pre-releases
+- Dev versions, which can be attached to sbpth table releases and pre-releases. When attached to a
   pre-release the dev version is ordered just below the normal pre-release, however when attached to
   a stable version, the dev version is sorted before a pre-releases
-* pre-release handling is a mess: "Pre-releases of any kind, including developmental releases, are
+- Pre-release handling is a mess: "Pre-releases of any kind, including developmental releases, are
   implicitly excluded from all version specifiers, unless they are already present on the system,
   explicitly requested by the user, or if the only available version that satisfies the version
   specifier is a pre-release.". This means that we can't say whether a specifier matches without
   also looking at the environment
-* pre-release vs. pre-release incl. dev is fuzzy
-* local versions on top of all the others, which are added with a + and have implicitly typed string
+- Pre-release vs. pre-release incl. dev is fuzzy
+- Local versions on top of all the others, which are added with a + and have implicitly typed string
   and number segments
-* no semver-caret (`^`), but a pseudo-semver tilde (`~=`)
-* ordering contradicts matching: We have, e.g., `1.0+local > 1.0` when sorting, but `==1.0` matches
+- No semver-caret (`^`), but a pseudo-semver tilde (`~=`)
+- Ordering contradicts matching: We have, e.g., `1.0+local > 1.0` when sorting, but `==1.0` matches
   `1.0+local`. While the ordering of versions itself is a total order the version matching needs to
   catch all sorts of special cases