[bug#51957] [PATCH] gnu: xfce-weather-plugin: Fix build by depending on libsoup2.

[Kaelyn]

I forgot to update the subject line before sending the email. This patch is 
based on core-updates-frozen, fixing a build issue I encountered:

checking pkg-config is at least version 0.9.0... yes
checking for libsoup-2.4 >= 2.42.0... not found
*** The required package libsoup-2.4 was not found on your system.
*** Please install libsoup-2.4 (atleast version 2.42.0) or adjust
*** the PKG_CONFIG_PATH environment variable if you
*** installed the package in a nonstandard prefix so that
*** pkg-config is able to find it.
error: in phase 'configure': uncaught exception:
%exception #<&invoke-error program: 
"/gnu/store/vx6vfbmmazvfi7vp8xyjn2mcyylvw9gn-bash-minimal-5.1.8/bin/bash" 
arguments: ("./configure" 
"CONFIG_SHELL=/gnu/store/vx6vfbmmazvfi7vp8xyjn2mcyylvw9gn-bash-minimal-5.1.8/bin/bash"
 
"SHELL=/gnu/store/vx6vfbmmazvfi7vp8xyjn2mcyylvw9gn-bash-minimal-5.1.8/bin/bash" 
"--prefix=/gnu/store/sf3l4yvm4hg2h1778kp10hzhmcbg4axq-xfce4-weather-plugin-0.11.0"
 "--enable-fast-install" "--build=x86_64-unknown-linux-gnu") exit-status: 1 
term-signal: #f stop-signal: #f>
phase `configure' failed after 1.3 seconds