chore(deps): update flashbots/mev-boost docker tag to v1.12.0 (#416)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [flashbots/mev-boost](https://redirect.github.com/flashbots/mev-boost)
| minor | `1.10.1` → `1.12.0` |

---

### Release Notes

<details>
<summary>flashbots/mev-boost (flashbots/mev-boost)</summary>

###
[`v1.12.0`](https://redirect.github.com/flashbots/mev-boost/compare/v1.11.0...v1.12.0)

[Compare
Source](https://redirect.github.com/flashbots/mev-boost/compare/v1.11.0...v1.12.0)

###
[`v1.11.0`](https://redirect.github.com/flashbots/mev-boost/compare/v1.10.1...v1.11.0)

[Compare
Source](https://redirect.github.com/flashbots/mev-boost/compare/v1.10.1...v1.11.0)

</details>

---

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compose-mev.yml

@@ -29,7 +29,7 @@ services:
 
   mev-mevboost:
     profiles: [mev-mevboost]
-    image: flashbots/mev-boost:${MEV_MEVBOOST_VERSION:-1.10.1}
+    image: flashbots/mev-boost:${MEV_MEVBOOST_VERSION:-1.12.0}
     command: |
       -${NETWORK}
       -loglevel=debug