fix: update theme version to 9.2.8

Author: clarkmcadoo

package.json

@@ -9,7 +9,7 @@
     "@emotion/styled": "^11.3.0",
     "@mdx-js/mdx": "^1.6.22",
     "@mdx-js/react": "^1.6.22",
-    "@newrelic/gatsby-theme-newrelic": "9.1.0",
+    "@newrelic/gatsby-theme-newrelic": "9.2.8",
     "@splitsoftware/splitio-react": "^1.2.4",
     "date-fns": "^2.17.0",
     "feather-icons": "^4.28.0",