Update dependency juju/juju to v2.9.49 (#253)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [juju/juju](https://togithub.com/juju/juju) | patch | `2.9.45` ->
`2.9.49` |

---

### Release Notes

<details>
<summary>juju/juju (juju/juju)</summary>

### [`v2.9.49`](https://togithub.com/juju/juju/releases/tag/v2.9.49):
Juju 2.9.49

[Compare
Source](https://togithub.com/juju/juju/compare/v2.9.47...v2.9.49)

### The Juju team is proud to release Juju 2.9.49!

This is a point release to the stable 2.9 series of Juju.

Checkout the [Juju 2.9.49 Release
Notes](https://discourse.charmhub.io/t/roadmap-releases/5064)

</details>

---

### Configuration

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defined).

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are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

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this box

---

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.github/workflows/ci.yaml

@@ -73,7 +73,7 @@ jobs:
       fail-fast: false
       matrix:
         juju:
-          - agent: 2.9.45  # renovate: juju-agent-pin-minor
+          - agent: 2.9.49  # renovate: juju-agent-pin-minor
             libjuju: ^2
             allure: false
           - agent: 3.4.3  # renovate: juju-agent-pin-minor