Run port forwarder and reverse proxy in order

[int128]

This changes to run the components in order.

Run a port forwarder and reverse proxy, and waits for them, as follows:

1. Run a port forwarder.
2. When the port forwarder is ready, run a reverse proxy.
3. When the reverse proxy is ready, open the browser.

When the context is canceled,

• Shut down the port forwarder.
• Shut down the reverse proxy.

[codecov-io]

Codecov Report

Merging #24 into master will increase coverage by 9.09%.
The diff coverage is 95.08%.

@@            Coverage Diff             @@
##           master      #24      +/-   ##
==========================================
+ Coverage   77.27%   86.36%   +9.09%     
==========================================
  Files           1        1              
  Lines          44       88      +44     
==========================================
+ Hits           34       76      +42     
- Misses          6        7       +1     
- Partials        4        5       +1

Impacted Files	Coverage Δ
pkg/usecases/authproxy/auth_proxy.go	86.36% <95.08%> (+9.09%)	⬆️

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