fix: optional smtp block should not override remote

[sweatybridge]

What kind of change does this PR introduce?

Bug fix

What is the new behavior?

If [auth.email.smtp] is not declared in config.toml, skip pushing the config to remote.

Also adds a enabled field to allow explicit disabling of smtp.

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 12215182885

Details

• 28 of 41 (68.29%) changed or added relevant lines in 3 files are covered.
• 8 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.07%) to 59.903%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/config/auth.go	26	39	66.67%

Files with Coverage Reduction	New Missed Lines	%
internal/debug/postgres.go	3	64.86%
internal/gen/keys/keys.go	5	12.9%

Totals
Change from base Build 12214394323:	-0.07%
Covered Lines:	7658
Relevant Lines:	12784

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💛 - Coveralls