chore(priority-alerts): Remove high priority alert condition

[snigdhas]

Cleanup the old high priority alert condition now that existing alerts have been migrated.

[codecov[bot]]

Codecov Report

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

Project coverage is 79.82%. Comparing base (da61e5a) to head (afe950f). Report is 2 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #70105 +/- ## ========================================== - Coverage 79.82% 79.82% -0.01% ========================================== Files 6504 6503 -1 Lines 289378 289333 -45 Branches 49834 49825 -9 ========================================== - Hits 230992 230950 -42 + Misses 57975 57972 -3 Partials 411 411 ``` | [Files](https://app.codecov.io/gh/getsentry/sentry/pull/70105?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry) | Coverage Δ | | |---|---|---| | [...entry/api/endpoints/project\_rules\_configuration.py](https://app.codecov.io/gh/getsentry/sentry/pull/70105?src=pr&el=tree&filepath=src%2Fsentry%2Fapi%2Fendpoints%2Fproject_rules_configuration.py&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry#diff-c3JjL3NlbnRyeS9hcGkvZW5kcG9pbnRzL3Byb2plY3RfcnVsZXNfY29uZmlndXJhdGlvbi5weQ==) | `100.00% <ø> (ø)` | | ... and [6 files with indirect coverage changes](https://app.codecov.io/gh/getsentry/sentry/pull/70105/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=getsentry)