feat: support custom migration name for db pull

[sweatybridge]

What kind of change does this PR introduce?

feature
closes #1612

What is the new behavior?

$ supabase db pull my_schema
Connecting to remote database...
Setting up initial schema....
Creating custom roles supabase/roles.sql...
Applying migration 20230811162533_test.sql...
Schema written to supabase/migrations/20231025092542_my_schema.sql
Update remote migration history table? [Y/n] n
Finished supabase db pull.

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 6649959813

• 7 of 12 (58.33%) changed or added relevant lines in 4 files are covered.
• 8 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.08%) to 58.58%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
cmd/db.go	0	5	0.0%

Files with Coverage Reduction	New Missed Lines	%
internal/debug/postgres.go	3	64.86%
internal/gen/keys/keys.go	5	12.31%

Totals
Change from base Build 6649955047:	-0.08%
Covered Lines:	5670
Relevant Lines:	9679

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💛 - Coveralls