build(deps): bump acorn from 5.7.1 to 5.7.4 in /client

Bumps [acorn](https://github.com/acornjs/acorn) from 5.7.1 to 5.7.4.
- [Release notes](https://github.com/acornjs/acorn/releases)
- [Commits](https://github.com/acornjs/acorn/compare/5.7.1...5.7.4)

Signed-off-by: dependabot[bot] <support@github.com>

client/package-lock.json

@@ -24,9 +24,9 @@
       }
     },
     "acorn": {
-      "version": "5.7.1",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.1.tgz",
-      "integrity": "sha512-d+nbxBUGKg7Arpsvbnlq61mc12ek3EY8EQldM3GPAhWJ1UVxC6TDGbIvUMNU6obBX3i1+ptCIzV4vq0gFPEGVQ==",
+      "version": "5.7.4",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.4.tgz",
+      "integrity": "sha512-1D++VG7BhrtvQpNbBzovKNc1FLGGEE/oGe7b9xJm/RFHMBeUaUGpluV9RLjZa47YFdPcDAenEYuq9pQPcMdLJg==",
       "dev": true
     },
     "acorn-dynamic-import": {