Bump proj4 from 2.6.2 to 2.6.3

Bumps [proj4](https://github.com/proj4js/proj4js) from 2.6.2 to 2.6.3.
- [Release notes](https://github.com/proj4js/proj4js/releases)
- [Changelog](https://github.com/proj4js/proj4js/blob/master/changelog.md)
- [Commits](proj4js/proj4js@2.6.2...2.6.3)

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

Author: dependabot[bot]

package.json

@@ -128,7 +128,7 @@
     "mapv": "2.0.56",
     "ol": "6.4.3",
     "pbf": "3.2.1",
-    "proj4": "2.6.2",
+    "proj4": "2.6.3",
     "promise-polyfill": "8.2.0",
     "three": "0.121.1",
     "xlsx": "0.16.8",