Bump proj4 from 2.5.0 to 2.6.0

Bumps [proj4](https://github.com/proj4js/proj4js) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/proj4js/proj4js/releases)
- [Changelog](https://github.com/proj4js/proj4js/blob/master/changelog.md)
- [Commits](https://github.com/proj4js/proj4js/compare/2.5.0...2.6.0)

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

package-lock.json

@@ -8953,9 +8953,9 @@
       "dev": true
     },
     "proj4": {
-      "version": "2.5.0",
-      "resolved": "https://registry.npmjs.org/proj4/-/proj4-2.5.0.tgz",
-      "integrity": "sha512-XZTRT7OPdLzgvtTqL8DG2cEj8lYdovztOwiwpwRSYayOty5Ipf3H68dh/fiL+HKDEyetmQSMhkkMGiJoyziz3w==",
+      "version": "2.6.0",
+      "resolved": "https://registry.npmjs.org/proj4/-/proj4-2.6.0.tgz",
+      "integrity": "sha512-ll2WyehUFOyzEZtN8hAiOTmZpuDCN5V+4A/HjhPbhlwVwlsFKnIHSZ3l3uhzgDndHjoL2MyERFGe9VmXN4rYUg==",
       "dev": true,
       "requires": {
         "mgrs": "1.0.0",

package.json

@@ -84,7 +84,7 @@
     "ol-mapbox-style": "^5.0.2",
     "pixelmatch": "^5.1.0",
     "pngjs": "^3.4.0",
-    "proj4": "2.5.0",
+    "proj4": "2.6.0",
     "puppeteer": "~1.20.0",
     "rollup": "^1.25.1",
     "rollup-plugin-babel": "^4.3.3",