Offer a way to disable tab-reloading at launch on Chromium-based browsers

Related discussion:
- a0a9497#commitcomment-62560291

The behavior could be seen as annoying to some users, and before
this commit there is no way to opt-out of the behavior, introduced
in 1.40.0.

This commit is only intended for Chromium version of uBO, and
setting `suspendTabsUntilReady` to `no` will prevent active tab
reload at launch once filter lists are all loaded.

In next release, there will be a setting in the "Filter lists"
pane to easily control the behavior and `suspendTabsUntilReady`
will be removed.

Author: gorhill

src/js/traffic.js

@@ -1150,8 +1150,8 @@ const webRequest = {
             // Mitigation: force-reload active tabs for environments not
             // supporting suspended network request listeners.
             if (
-                vAPI.net.canSuspend() !== true ||
-                µb.hiddenSettings.suspendTabsUntilReady === 'no'
+                vAPI.net.canSuspend() !== true &&
+                µb.hiddenSettings.suspendTabsUntilReady === 'unset'
             ) {
                 const tabs = await vAPI.tabs.query({
                     active: true,