pkg/utils, test/system: Preserve the Konsole profile, tab and window

Konsole injects the name of the current profile, and the identifiers
of the current tab and window into the process running inside it
through the KONSOLE_PROFILE_NAME, KONSOLE_DBUS_SESSION and
KONSOLE_DBUS_WINDOW environment variables respectively [1,2,3].  These
are used by programs like Neovim to detect the terminal features
supported by Konsole [4,5], or by users to save the shell's history
separately for each profile, tab or window [6].

These environment variables are not meant to be set by the shell's
start-up scripts, but directly by Konsole, and hence needs to be
preserved across the host operating system and Toolbx container.

Note that KONSOLE_PROFILE_NAME was later removed from Konsole [7].
However, Neovim still uses it, so it's better to preserve it.

[1] Konsole commit debfec2eb3c8ede8
    https://invent.kde.org/utilities/konsole/-/commit/debfec2eb3c8ede8
    https://bugs.kde.org/show_bug.cgi?id=227296

[2] Konsole commit fcd815256c3729f2
    https://invent.kde.org/utilities/konsole/-/commit/fcd815256c3729f2

[3] Konsole commit 07cddfe302233c35
    https://invent.kde.org/utilities/konsole/-/commit/07cddfe302233c35
    https://bugs.kde.org/show_bug.cgi?id=276912
    https://bugs.kde.org/show_bug.cgi?id=281513
    https://bugs.kde.org/show_bug.cgi?id=292309

[4] Neovim commit 5fc4c2d442f01ab5
    neovim/neovim@5fc4c2d442f01ab5
    neovim/neovim#3129

[5] Neovim commit 3ccd59ee8216f3da
    neovim/neovim@3ccd59ee8216f3da
    neovim/neovim#6432
    neovim/neovim#6429
    neovim/neovim#6430

[6] https://userbase.kde.org/Konsole/en

[7] Konsole commit 9e3a30fdca2078e0
    https://invent.kde.org/utilities/konsole/-/commit/9e3a30fdca2078e0
    https://bugs.kde.org/show_bug.cgi?id=406955

containers#1449
containers#1696
containers#1698

Author: bkoropoff

src/pkg/utils/utils.go

@@ -95,6 +95,9 @@ var (
 		"HOME",
 		"KDE_FULL_SESSION",
 		"KDE_SESSION_VERSION",
+		"KONSOLE_DBUS_SESSION",
+		"KONSOLE_DBUS_WINDOW",
+		"KONSOLE_PROFILE_NAME",
 		"KONSOLE_VERSION",
 		"LANG",
 		"SHELL",