fix: unset GTK_THEME

Fixes issues with custom themes breaking colors in the history list.

Ref: #152

src/main.rs

@@ -17,6 +17,9 @@ fn main() -> ExitCode {
     // Initialize logger
     pretty_env_logger::init();
 
+    // ensure Adwaita will be used
+    std::env::remove_var("GTK_THEME");
+
     // Prepare i18n
     gettextrs::setlocale(LocaleCategory::LcAll, "");
     gettextrs::bindtextdomain(GETTEXT_PACKAGE, LOCALEDIR).expect("Unable to bind the text domain");