chore(deps): update oven-sh/setup-bun digest to b7a1c7c (#1508)

This PR contains the following updates:

| Package | Type | Update | Change | OpenSSF |
|---|---|---|---|---|
| [oven-sh/setup-bun](https://redirect.github.com/oven-sh/setup-bun)
([changelog](https://redirect.github.com/oven-sh/setup-bun/compare/735343b667d3e6f658f44d0eca948eb6282f2b76..b7a1c7ccf290d58743029c4f6903da283811b979))
| action | digest | `735343b` → `b7a1c7c` | [![OpenSSF
Scorecard](https://api.securityscorecards.dev/projects/github.com/oven-sh/setup-bun/badge)](https://securityscorecards.dev/viewer/?uri=github.com/oven-sh/setup-bun)
|

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<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Update the e2e workflow to use the latest v2 digest of oven-sh/setup-bun
(b7a1c7c). Keeps the action pinned for reproducibility while pulling the
latest fixes.

- **Dependencies**
- Bump oven-sh/setup-bun from 735343b to b7a1c7c in
.github/workflows/e2e.yml

<sup>Written for commit 5e7082e.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/e2e.yml

@@ -48,7 +48,7 @@ jobs:
             ~/.bun/install/cache
 
       - name: Setup Bun
-        uses: oven-sh/setup-bun@735343b667d3e6f658f44d0eca948eb6282f2b76 # v2
+        uses: oven-sh/setup-bun@b7a1c7ccf290d58743029c4f6903da283811b979 # v2
         with:
           bun-version-file: .bun-version