Bump acorn from 5.7.3 to 5.7.4

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

yarn.lock

@@ -2194,16 +2194,11 @@ acorn-walk@^6.0.1:
   integrity sha512-7evsyfH1cLOCdAzZAd43Cic04yKydNx0cF+7tiA19p1XnLLPU4dpCQOqpjqwokFe//vS0QqfqqjCS2JkiIs0cA==
 
 acorn@^5.0.0:
-  version "5.7.3"
-  resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.7.3.tgz#67aa231bf8812974b85235a96771eb6bd07ea279"
-  integrity sha512-T/zvzYRfbVojPWahDsE5evJdHb3oJoQfFbsrKM7w5Zcs++Tr257tia3BmMP8XYVjp1S9RZXQMh7gao96BlqZOw==
+  version "5.7.4"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.7.4.tgz#3e8d8a9947d0599a1796d10225d7432f4a4acf5e"
+  integrity sha512-1D++VG7BhrtvQpNbBzovKNc1FLGGEE/oGe7b9xJm/RFHMBeUaUGpluV9RLjZa47YFdPcDAenEYuq9pQPcMdLJg==
 
-acorn@^6.0.1, acorn@^6.0.4:
-  version "6.4.0"
-  resolved "https://registry.yarnpkg.com/acorn/-/acorn-6.4.0.tgz#b659d2ffbafa24baf5db1cdbb2c94a983ecd2784"
-  integrity sha512-gac8OEcQ2Li1dxIEWGZzsp2BitJxwkwcOm0zHAJLcPJaVvm58FRnk6RkuLRpU1EujipU2ZFODv2P9DLMfnV8mw==
-
-acorn@^6.4.1:
+acorn@^6.0.1, acorn@^6.0.4, acorn@^6.4.1:
   version "6.4.1"
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-6.4.1.tgz#531e58ba3f51b9dacb9a6646ca4debf5b14ca474"
   integrity sha512-ZVA9k326Nwrj3Cj9jlh3wGFutC2ZornPNARZwsNYqQYgN0EsV2d53w5RN/co65Ohn4sUAUtb1rSUAOD6XN9idA==