crosscluster/logical: support external://

[dt]

Release note: none. Epic: none.

[cockroach-teamcity]

This change is 

[stevendanna]

bors r=stevendanna

[craig[bot]]

Build failed:

• check_generated_code

[stevendanna]

bors retry

[craig[bot]]

Build failed:

• unit_tests

[stevendanna]

Probably just needs a rebase against your other small cleanup PR.

pkg/ccl/crosscluster/logical/logical_replication_job_test.go:155:11: undefined: url

[dt]

TFTR!

bors r+

[craig[bot]]

Build failed:

• examples_orms

[stevendanna]

bors retry

[craig[bot]]

Build failed (retrying...):

• local_roachtest

[craig[bot]]

Build failed:

• acceptance

[msbutler]

bors r-

[msbutler]

@dt cockroach is not compiling. i think you need to rebase. Craig's errors are misleading. Opened a thread in dev inf about this.

[dt]

bors r+

[craig[bot]]

Build succeeded:

• acceptance
• macos_amd64_build
• linux_amd64_build
• local_roachtest
• examples_orms
• windows_build
• local_roachtest_fips
• linux_arm64_build
• lint
• docker_image_amd64
• unit_tests
• linux_amd64_fips_build
• check_generated_code
• macos_arm64_build