chore: update dependency babel-plugin-istanbul to v7

Author: renovate[bot]

package-lock.json

@@ -58,7 +58,7 @@
     "@svgr/webpack": "^8.1.0",
     "@testing-library/preact": "^3.2.4",
     "babel-loader": "^9.1.2",
-    "babel-plugin-istanbul": "^6.1.1",
+    "babel-plugin-istanbul": "^7.0.0",
     "camunda-dmn-moddle": "^1.3.0",
     "chai": "^4.4.1",
     "cross-env": "^7.0.3",