Bump prismjs from 1.25.0 to 1.27.0 in /web-app (#585)

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.25.0 to 1.27.0.
- [Release notes](https://github.com/PrismJS/prism/releases)
- [Changelog](https://github.com/PrismJS/prism/blob/master/CHANGELOG.md)
- [Commits](PrismJS/prism@v1.25.0...v1.27.0)

---
updated-dependencies:
- dependency-name: prismjs
  dependency-type: direct:production
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

web-app/package.json

@@ -35,7 +35,7 @@
     "js-yaml": "4.1.0",
     "markdown-it": "12.3.2",
     "markdown-it-emoji": "2.0.0",
-    "prismjs": "1.25.0",
+    "prismjs": "1.27.0",
     "react": "16.13.1",
     "react-addons-css-transition-group": "15.6.2",
     "react-dom": "16.13.1",

web-app/yarn.lock

@@ -13763,10 +13763,10 @@ pretty-hrtime@^1.0.3:
   resolved "https://registry.yarnpkg.com/pretty-hrtime/-/pretty-hrtime-1.0.3.tgz#b7e3ea42435a4c9b2759d99e0f201eb195802ee1"
   integrity sha1-t+PqQkNaTJsnWdmeDyAesZWALuE=
 
-prismjs@1.25.0, prismjs@^1.21.0:
-  version "1.25.0"
-  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.25.0.tgz#6f822df1bdad965734b310b315a23315cf999756"
-  integrity sha512-WCjJHl1KEWbnkQom1+SzftbtXMKQoezOCYs5rECqMN+jP+apI7ftoflyqigqzopSO3hMhTEb0mFClA8lkolgEg==
+prismjs@1.27.0, prismjs@^1.21.0:
+  version "1.27.0"
+  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.27.0.tgz#bb6ee3138a0b438a3653dd4d6ce0cc6510a45057"
+  integrity sha512-t13BGPUlFDR7wRB5kQDG4jjl7XeuH6jbJGt11JHPL96qwsEHNX2+68tFXqc1/k+/jALsbSWJKUOT/hcYAZ5LkA==
 
 prismjs@~1.22.0:
   version "1.22.0"