build(deps): update axllent/mailpit docker tag to v1.31.5 (#13443)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [axllent/mailpit](https://mailpit.axllent.org)
([source](https://redirect.github.com/axllent/mailpit)) | patch |
`v1.31.4` → `v1.31.5` |

---

### Release Notes

<details>
<summary>axllent/mailpit</summary>

###
[`v1.31.5`](https://redirect.github.com/axllent/mailpit/blob/HEAD/CHANGELOG.md#v1315)

[Compare
Source](https://redirect.github.com/axllent/mailpit/compare/v1.31.4...v1.31.5)

##### Chore

- Add gosec #nosec annotations and set explicit Content-Type on error
responses
- Update Go dependencies
- Update node dependencies

##### Fix

- Escape `_` and `%` in search terms so they match literally
([#&#8203;742](https://redirect.github.com/axllent/mailpit/issues/742))
- Match `&` and `\` in address searches
([#&#8203;743](https://redirect.github.com/axllent/mailpit/issues/743))
- Validate AUTH parameter in MAIL FROM command
([#&#8203;744](https://redirect.github.com/axllent/mailpit/issues/744))
- MAIL FROM parameters must be space-separated per RFC 5321

##### Test

- Include additional tests for MAIL FROM parameters

</details>

---

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internal/suites/example/compose/smtp/compose.yml

@@ -5,7 +5,7 @@
 ---
 services:
   smtp:
-    image: 'axllent/mailpit:v1.31.4'
+    image: 'axllent/mailpit:v1.31.5'
     cpus: 2
     mem_limit: 1g
     volumes:

internal/suites/example/kube/mail/mail.yml

@@ -22,7 +22,7 @@ spec:
     spec:
       containers:
         - name: mailpit
-          image: axllent/mailpit:v1.31.4
+          image: axllent/mailpit:v1.31.5
           ports:
             - containerPort: 1025
             - containerPort: 8025