Bump y18n from 4.0.0 to 4.0.3 in /web-app

Bumps [y18n](https://github.com/yargs/y18n) from 4.0.0 to 4.0.3.
- [Release notes](https://github.com/yargs/y18n/releases)
- [Changelog](https://github.com/yargs/y18n/blob/y18n-v4.0.3/CHANGELOG.md)
- [Commits](yargs/y18n@v4.0.0...y18n-v4.0.3)

---
updated-dependencies:
- dependency-name: y18n
  dependency-type: indirect
...

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

Author: dependabot[bot]

web-app/yarn.lock

@@ -16350,9 +16350,9 @@ xtend@^4.0.0, xtend@~4.0.1:
   integrity sha512-LKYU1iAXJXUgAXn9URjiu+MWhyUXHsvfp7mcuYm9dSUKK0/CjtrUwFAxD82/mCWbtLsGjFIad0wIsod4zrTAEQ==
 
 y18n@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.yarnpkg.com/y18n/-/y18n-4.0.0.tgz#95ef94f85ecc81d007c264e190a120f0a3c8566b"
-  integrity sha512-r9S/ZyXu/Xu9q1tYlpsLIsa3EeLXXk0VwlxqTcFRfg9EhMW+17kbt9G0NrgCmhGb5vT2hyhJZLfDGx+7+5Uj/w==
+  version "4.0.3"
+  resolved "https://registry.yarnpkg.com/y18n/-/y18n-4.0.3.tgz#b5f259c82cd6e336921efd7bfd8bf560de9eeedf"
+  integrity sha512-JKhqTOwSrqNA1NY5lSztJ1GrBiUodLMmIZuLiDaMRJ+itFd+ABVE8XBjOvIWL+rSqNDC74LCSFmlb/U4UZ4hJQ==
 
 yallist@^2.1.2:
   version "2.1.2"