Auto merge of #13996 - rust-lang:renovate/alpine-3.x, r=weihanglo

chore(deps): update alpine docker tag to v3.20

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| alpine | final | minor | `3.19` -> `3.20` |

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crates/cargo-test-support/containers/sshd/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.19
+FROM alpine:3.20
 
 RUN apk add --no-cache openssh git
 RUN ssh-keygen -A