feat(relocation): Store colliding users output

[azaslavsky]

Previously, we did not wait for the export-colliding-users CloudBuild task to finish before copying files. This caused the colliding-users.tar file associated with that export to be lost. With this change, we will ensure that it is retained.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 79.68%. Comparing base (53c0c8f) to head (30b436b).

:exclamation: Current head 30b436b differs from pull request most recent head a06c540. Consider uploading reports for the commit a06c540 to get more accurate results

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #69238 +/- ## =========================================== + Coverage 58.20% 79.68% +21.48% =========================================== Files 6234 6432 +198 Lines 275091 285985 +10894 Branches 47461 49301 +1840 =========================================== + Hits 160111 227897 +67786 + Misses 114538 57651 -56887 + Partials 442 437 -5 ``` | [Files](https://app.codecov.io/gh/getsentry/sentry/pull/69238?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry) | Coverage Δ | | |---|---|---| | [src/sentry/utils/relocation.py](https://app.codecov.io/gh/getsentry/sentry/pull/69238?src=pr&el=tree&filepath=src%2Fsentry%2Futils%2Frelocation.py&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry#diff-c3JjL3NlbnRyeS91dGlscy9yZWxvY2F0aW9uLnB5) | `98.13% <ø> (+59.38%)` | :arrow_up: | ... and [2016 files with indirect coverage changes](https://app.codecov.io/gh/getsentry/sentry/pull/69238/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry)