Add pixel for process creation, for both main and VPN processes

[CDRussell]

Task/Issue URL: https://app.asana.com/0/488551667048375/1206681496516579/f

Description

Adds process creation pixels, for both main app and VPN process.

Steps to test this PR

• [ ] Add logcat filter message~:"m_process_created"

Main app process

• [ ] Launch the app; verify you see m_process_created_main
• [ ] Background and restore the app; verify you do not see it again
• [ ] Kill the app and relaunch it; verify you do see it again

VPN process

• [ ] onboard through AppTP
• [ ] verify you see m_process_created_vpn in the logs

[CDRussell]

• #4208 👈
• develop

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