net-p2p/transmission: Switch from GTK3 to GTK4

[mattst88]

Closes: https://bugs.gentoo.org/900885

The diff between 4.0.3 (GTK3) and 4.0.3-r1 (GTK4) is

--- transmission-4.0.3.ebuild	2023-05-05 14:52:58.524449742 -0400
+++ transmission-4.0.3-r1.ebuild	2023-05-05 14:54:55.204243236 -0400
@@ -51,8 +51,8 @@
 	sys-libs/zlib:=
 	nls? ( virtual/libintl )
 	gtk? (
-		>=dev-cpp/gtkmm-3.24.0:3.0
-		>=dev-cpp/glibmm-2.60.0:2
+		>=dev-cpp/gtkmm-3.24.0:4.0
+		>=dev-cpp/glibmm-2.60.0:2.68
 		appindicator? ( dev-libs/libayatana-appindicator )
 	)
 	qt5? (
@@ -89,7 +89,7 @@
 
 		-DRUN_CLANG_TIDY=OFF
 
-		-DUSE_GTK_VERSION=3
+		-DUSE_GTK_VERSION=4
 		-DUSE_SYSTEM_EVENT2=ON
 		-DUSE_SYSTEM_DEFLATE=OFF
 		-DUSE_SYSTEM_DHT=OFF

Strangely CMakeLists.txt uses the same minimum versions for gtkmm and glibmm, regardless of whether GTK3 or GTK4 was chosen, so I've left the version requirements as they are.

[gentoo-repo-qa-bot]

Pull request CI report

Report generated at: 2023-05-05 19:08 UTC
Newest commit scanned: 8317eb6
Status: ✅ good

There are existing issues already. Please look into the report to make sure none of them affect the packages in question:
https://qa-reports.gentoo.org/output/gentoo-ci/dc54d4c673/output.html

[floppym]

If it works, feel free to merge it.

[floppym]

Please keep the live ebuild in sync. Feel free to make that change without review.