Update earthly/earthly digest to 08b0d1f (#102)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| earthly/earthly | digest | `c70b270` -> `08b0d1f` |

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.arg

@@ -1,3 +1,3 @@
 DOCKERHUB_USER=earthly
 IMAGE_NAME=dind
-EARTHLY_REPO_VERSION=c70b2701415f217058809ad08b303e01e29dcda7
+EARTHLY_REPO_VERSION=08b0d1ff1388b34d10ebb6a0164a7784cfbe9db2