Update actions/checkout action to v6 (#177)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | major | `v5.0.0` -> `v6.0.0` |

---

### Release Notes

<details>
<summary>actions/checkout (actions/checkout)</summary>

###
[`v6.0.0`](https://redirect.github.com/actions/checkout/compare/v5.0.1...v6.0.0)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v5.0.1...v6.0.0)

###
[`v5.0.1`](https://redirect.github.com/actions/checkout/releases/tag/v5.0.1)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v5.0.0...v5.0.1)

##### What's Changed

- Port v6 cleanup to v5 by
[@&#8203;ericsciple](https://redirect.github.com/ericsciple) in
[#&#8203;2301](https://redirect.github.com/actions/checkout/pull/2301)

**Full Changelog**:
<actions/checkout@v5...v5.0.1>

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "on the first day of the month" (UTC),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
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.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/jaegertracing/jaeger-idl).

<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0Mi4xOS45IiwidXBkYXRlZEluVmVyIjoiNDIuMTkuOSIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOlsiY2hhbmdlbG9nOmRlcGVuZGVuY2llcyJdfQ==-->

Signed-off-by: Mend Renovate <[email protected]>

Author: renovate-bot

.github/workflows/ci-lint-test.yml

@@ -21,7 +21,7 @@ jobs:
   generated-files-check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           submodules: recursive
       - name: Verify Protobuf types are up to date
@@ -33,7 +33,7 @@ jobs:
   go-mod-tidy-check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Verify go.mod files are up to date
         run: |
           go mod tidy && \
@@ -46,7 +46,7 @@ jobs:
       - uses: step-security/harden-runner@4d991eb9b905ef189e4c376166672c3f2f230481  # v2.11.0
         with:
           egress-policy: audit
-      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00 # v6.0.0
         with:
           go-version: 1.24.x

.github/workflows/ci-unit-tests.yml

@@ -25,7 +25,7 @@ jobs:
       with:
         egress-policy: audit
 
-    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00 # v6.0.0
       with:
@@ -46,7 +46,7 @@ jobs:
   test-code-gen:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: Init git submodules
       run: make init-submodule