Allow default zip metadata reader limit to be configurable

What does this MR do and why?

⚠ This MR needs the following MRs merged:

• Prefer flag.Args() over os.Args (!141578 - merged)
• New config.NewDefaultConfig() function (!141579 - merged)

This MR allows the previously hardcoded default zip metadata reader limit (104857600) to be configurable.

Related: Allow default zip metadata reader limit to be c... (#439016 - closed)