chore(deps): update node.js to a7a3b7e (#2870)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [node](https://redirect.github.com/nodejs/node) | stage | digest |
`7eaecf1` -> `a7a3b7e` |

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gcp/appengine/Dockerfile

@@ -1,5 +1,5 @@
 # Build the Javascript frontend
-FROM node:20.18@sha256:7eaecf12ba40043be19af57e2c7fba35d61f9b906128e3e4d11eda81b1ecb857 AS FRONTEND3_BUILD
+FROM node:20.18@sha256:a7a3b7ec6de4b11bb2d673b31de9d28c6da09c557ee65453672c8e4f754c23fc AS FRONTEND3_BUILD
 WORKDIR /build/frontend3
 
 # Install dependencies first for better caching