fix: load nested env files up to repo directory

[sweatybridge]

What kind of change does this PR introduce?

closes #1001

What is the new behavior?

Branching environments defaults to repo directory. In a monorepo setup, the supabase directory may be arbitrarily nested. So we find all parent .env files starting from the location of config.toml.

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 12789228787

Details

• 14 of 22 (63.64%) changed or added relevant lines in 1 file are covered.
• 7 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.03%) to 58.415%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/config/config.go	14	22	63.64%

Files with Coverage Reduction	New Missed Lines	%
internal/storage/rm/rm.go	2	89.53%
internal/gen/keys/keys.go	5	12.9%

Totals
Change from base Build 12781919307:	-0.03%
Covered Lines:	7587
Relevant Lines:	12988

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💛 - Coveralls