gnu: libgweather: Adjust to new timezone name.

* gnu/packages/gnome.scm (libgweather)[arguments]: In 'pre-check' phase,
update "Asia/Rangoon" timezone name.

gnu/packages/gnome.scm

@@ -2598,13 +2598,18 @@ service via the system message bus.")
                          "/share/zoneinfo"))
        #:phases
        (modify-phases %standard-phases
-         (add-before
-          'check 'pre-check
+         (add-before 'check 'pre-check
            (lambda* (#:key inputs #:allow-other-keys)
              (substitute* "data/check-timezones.sh"
                (("/usr/share/zoneinfo/zone.tab")
                 (string-append (assoc-ref inputs "tzdata")
                                "/share/zoneinfo/zone.tab")))
+
+             ;; 'Asia/Rangoon' was renamed in tzdata-2016:
+             ;; <https://github.com/eggert/tz/commit/4368251ebf11310a4aadccd1910daeac9080c501>.
+             (substitute* "data/Locations.xml"
+               (("Asia/Rangoon")
+                "Asia/Yangon"))
             #t)))))
     (native-inputs
      `(("glib:bin" ,glib "bin") ; for glib-mkenums