patch 9.1.1370: CI Tests favor GTK2 over GTK3

Problem:  CI Tests favor GTK2 over GTK3
Solution: Install GTK3 dependencies and debug packages for CI workflows,
          update ASAN suppression list, update required dependency
          checks for the tests (Drew Vogel)

closes: #17253

Signed-off-by: Drew Vogel <dvogel@github>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_termencoding.vim b/src/testdir/test_termencoding.vim
index 9b7f487..a45ff84 100644
--- a/src/testdir/test_termencoding.vim
+++ b/src/testdir/test_termencoding.vim
@@ -15,6 +15,7 @@
 " running with 'encoding' "euc-jp".  We need to make sure the text is in the
 " right encoding, this is a bit tricky.
 func Test_termencoding_euc_jp()
+  CheckScreendump
   new
   call setline(1, 'E89: バッファ %ld の変更は保存されていません (! で変更を破棄)')
   write ++enc=euc-jp Xeuc_jp.txt