fix(chttpd): Always show browser login popup

[big-r81]

Always show the browser login popup, no matter which option of require_valid_user or require_valid_user_except_for_up is set.

[big-r81]

Additional finding

Abbreviations

rvu = request_valid_user rvuefu = request_valid_user_except_for_up

Before #5370 (use auth for live node checks)

rvu	rvuefu	start dev server
false	false	false
true	false	false
false	true	false
true	true	false

After #5370

rvu	rvuefu	start dev server
false	false	true
true	false	true
false	true	false
true	true	true

With this PR

rvu	rvuefu	start dev server
false	false	true
true	false	true
false	true	true
true	true	true