Bump acorn from 5.7.3 to 5.7.4 in /app

Bumps [acorn](https://github.com/acornjs/acorn) from 5.7.3 to 5.7.4.
- [Release notes](https://github.com/acornjs/acorn/releases)
- [Commits](https://github.com/acornjs/acorn/compare/5.7.3...5.7.4)

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

app/package-lock.json

@@ -111,9 +111,9 @@
       }
     },
     "acorn": {
-      "version": "7.0.0",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-7.0.0.tgz",
-      "integrity": "sha512-PaF/MduxijYYt7unVGRuds1vBC9bFxbNf+VWqhOClfdgy7RlVkQqt610ig1/yxTgsDIfW1cWDel5EBbOy3jdtQ==",
+      "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": {
@@ -817,9 +817,9 @@
       },
       "dependencies": {
         "acorn": {
-          "version": "6.3.0",
-          "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.3.0.tgz",
-          "integrity": "sha512-/czfa8BwS88b9gWQVhc8eknunSA2DoJpJyTQkhheIf5E48u1N0R4q/YxxsAeqRrmK9TQ/uYfgLDfZo91UlANIA==",
+          "version": "6.4.1",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.4.1.tgz",
+          "integrity": "sha512-ZVA9k326Nwrj3Cj9jlh3wGFutC2ZornPNARZwsNYqQYgN0EsV2d53w5RN/co65Ohn4sUAUtb1rSUAOD6XN9idA==",
           "dev": true
         },
         "ansi-styles": {
@@ -2951,12 +2951,6 @@
         "simple-html-tokenizer": "^0.5.7"
       },
       "dependencies": {
-        "acorn": {
-          "version": "5.7.3",
-          "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.3.tgz",
-          "integrity": "sha512-T/zvzYRfbVojPWahDsE5evJdHb3oJoQfFbsrKM7w5Zcs++Tr257tia3BmMP8XYVjp1S9RZXQMh7gao96BlqZOw==",
-          "dev": true
-        },
         "acorn-dynamic-import": {
           "version": "3.0.0",
           "resolved": "https://registry.npmjs.org/acorn-dynamic-import/-/acorn-dynamic-import-3.0.0.tgz",
@@ -3087,6 +3081,14 @@
         "@types/estree": "0.0.39",
         "@types/node": "^12.7.2",
         "acorn": "^7.0.0"
+      },
+      "dependencies": {
+        "acorn": {
+          "version": "7.1.1",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-7.1.1.tgz",
+          "integrity": "sha512-add7dgA5ppRPxCFJoAGfMDi7PIBXq1RtGo7BhbLaxwrXPOmw8gq48Y9ozT01hUKy9byMjlR20EJhu5zlkErEkg==",
+          "dev": true
+        }
       }
     },
     "rollup-plugin-babel": {