Update earthly/earthly digest to 8073987 (#60)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| earthly/earthly | digest | `f5bd4ae` -> `8073987` |

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.arg

@@ -1,3 +1,3 @@
 DOCKERHUB_USER=earthly
 IMAGE_NAME=dind
-EARTHLY_REPO_VERSION=f5bd4aeb7259485b18ffccd3eecaaa2ae987919c
+EARTHLY_REPO_VERSION=807398730a099ca1f0cf20c04099245919cf800e