Bump canvg from 3.0.10 to 4.0.3 in /src/openlayers

Bumps [canvg](https://github.com/canvg/canvg) from 3.0.10 to 4.0.3.
- [Release notes](https://github.com/canvg/canvg/releases)
- [Changelog](https://github.com/canvg/canvg/blob/master/CHANGELOG.md)
- [Commits](https://github.com/canvg/canvg/commits/v4.0.3)

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

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

Author: dependabot[bot]

src/openlayers/package.json

@@ -20,7 +20,7 @@
     "@turf/turf": "6.5.0",
     "mapv": "2.0.62",
     "ol": "7.5.2",
-    "canvg": "3.0.10",
+    "canvg": "4.0.3",
     "lodash.clonedeep": "^4.5.0",
     "lodash.remove": "^4.7.0",
     "lodash.difference": "^4.5.0",