backup: fix alter backup schedule failing on uri with spaces

[kev-cao]

ALTER BACKUP SCHEDULE being run on a backup schedule whose URI contains spaces would fail with error ERROR: parse "'gs://cockroachdb-backup-testing/kevin spacey?AUTH=implicit'": first path segment in URL cannot contain colon.

This was caused by the fact that despite the FmtBareStrings flag being used, the space character is considered one of the "special characters" outlined in its doc that causes the string to remain wrapped with quotes. Passing this quoted string to url.Parse fails.

Fixes: #134861

Release note (bug fix): ALTER BACKUP SCHEDULE no longer fails on schedules whose collection URI contains a space.

[blathers-crl]

It looks like your PR touches production code but doesn't add or edit any test code. Did you consider adding tests to your PR?

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[cockroach-teamcity]

This change is 

[msbutler]

Do we need to change how processInto parses uris too?

[kev-cao]

@msbutler Nope, it does not need to. That being said, I'll update the tests so that it also includes it

[kev-cao]

TFTR!

bors r=msbutler

[craig]

Build succeeded:

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

[kev-cao]

blathers backport 24.1 24.2 24.3

[blathers-crl]

Based on the specified backports for this PR, I applied new labels to the following linked issue(s). Please adjust the labels as needed to match the branches actually affected by the issue(s), including adding any known older branches.

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Issue #134861: branch-release-24.1, branch-release-24.2, branch-release-24.3.

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[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error creating merge commit from bbac419 to blathers/backport-release-24.1-137948: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.1 failed. See errors above.

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error creating merge commit from bbac419 to blathers/backport-release-24.2-137948: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.2 failed. See errors above.

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error creating merge commit from bbac419 to blathers/backport-release-24.3-137948: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.3 failed. See errors above.

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