Update earthly/earthly digest to b59b70d (#40)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| earthly/earthly | digest | `22b8e7c` -> `b59b70d` |

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.arg

@@ -1,3 +1,3 @@
 DOCKERHUB_USER=earthly
 IMAGE_NAME=dind
-EARTHLY_REPO_VERSION=22b8e7c901b2b3b8c6a7ba403b8fd8dd7f61277a
+EARTHLY_REPO_VERSION=b59b70d6559ddeae11daa6a8b025581d4806a385