git: fix the pkgver

In 363b1e7 (git: drop the commit hash from pkgver for MSYS2
compatibility, 2025-11-14), I dropped the auto-updating logic of
`pkgver`, forgetting that Git for Windows' automation would not update
that line. As a consequence, the Pacman packages built as part of Git
for Windows' v2.53.0 release process incorrectly reference the previous
pkgver and the Git for Windows SDKs do not enjoy the update.

Let's fix that by switching to a Bash'ism (which is fine, given that
`makepkg` contains _so many_ Bash'isms that it is highly implausible
that it will ever work with any other Unix shell).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

mingw-w64-git/PKGBUILD

@@ -18,7 +18,7 @@ pkgname=("${MINGW_PACKAGE_PREFIX}-${_realname}"
 	 "${MINGW_PACKAGE_PREFIX}-${_realname}-gui"
 	 "${MINGW_PACKAGE_PREFIX}-${_realname}-for-windows-addons")
 tag=2.53.0.windows.1
-pkgver=2.52.0.1
+pkgver=${tag/.windows./.}
 pkgrel=1
 pkgdesc="The fast distributed version control system (mingw-w64)"
 arch=('any')