docs: update redirecting url

A php.net URL in `docs/Versions.md` is redirecting to www.php.net, so
this updates the URL to avoid the redirection.

docs/Versions.md

@@ -9,7 +9,7 @@ Versioned formulae we include in [homebrew/core](https://github.com/homebrew/hom
 * Versioned software should build on all of Homebrew's supported versions of macOS.
 * Versioned formulae should differ in major/minor (not patch) versions from the current stable release. This is because patch versions indicate bug or security updates, and we want to ensure you apply security updates.
 * Unstable versions (alpha, beta, development versions) are not acceptable for versioned (or unversioned) formulae.
-* Upstream should have a release branch for each formula version, and have an explicit policy of releasing security updates for each version when necessary. For example, [PHP 7.0 was not a supported version but PHP 7.2 was](https://php.net/supported-versions.php) in January 2020. By contrast, most software projects are structured to only release security updates for their latest versions, so their earlier versions are not eligible for versioning.
+* Upstream should have a release branch for each formula version, and have an explicit policy of releasing security updates for each version when necessary. For example, [PHP 7.0 was not a supported version but PHP 7.2 was](https://www.php.net/supported-versions.php) in January 2020. By contrast, most software projects are structured to only release security updates for their latest versions, so their earlier versions are not eligible for versioning.
 * Versioned formulae should share a codebase with the main formula. If the project is split into a different repository, we recommend creating a new formula (`formula2` rather than `formula@2` or `formula@1`).
 * Formulae that depend on versioned formulae must not depend on the same formulae at two different versions twice in their recursive dependencies. For example, if you depend on `[email protected]` and `foo`, and `foo` depends on `openssl` then you must instead use `openssl`.
 * Versioned formulae should only be linkable at the same time as their non-versioned counterpart if the upstream project provides support for it, e.g. by using suffixed binaries. If this is not possible, use `keg_only :versioned_formula` to allow users to have multiple versions installed at once.