fix: set a fallback redirectUri for external provider

[singh-inder]

What kind of change does this PR introduce?

Fix #5216 regression

What is the current behavior?

After #5092, cli no longer sets a default redirectUri for external providers when not defined in config.toml. Also, config file mentions there will be a default redirectUri set if not provided.

cli/pkg/config/templates/config.toml

Lines 322 to 323 in 893c284

	# Overrides the default auth callback URL derived from auth.external_url.
	redirect_uri = ""

What is the new behavior?

set default redirectUri to Auth.JwtIssuer/callback if not provided

[coveralls]

Coverage Report for CI Build 25853445741

Coverage decreased (-0.01%) to 63.744%

Details

• Coverage decreased (-0.01%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 9 coverage regressions across 2 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

9 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
internal/utils/git.go	5	57.14%
internal/start/start.go	4	64.72%

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Coverage Stats

Relevant Lines:	15680
Covered Lines:	9995
Line Coverage:	63.74%
Coverage Strength:	7.06 hits per line

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💛 - Coveralls