Bump reveal.js from 3.9.2 to 4.3.0 in /docs/asciidoctor-reveal.js-master

Bumps [reveal.js](https://github.com/hakimel/reveal.js) from 3.9.2 to 4.3.0.
- [Release notes](https://github.com/hakimel/reveal.js/releases)
- [Commits](hakimel/reveal.js@3.9.2...4.3.0)

---
updated-dependencies:
- dependency-name: reveal.js
  dependency-type: direct:production
...

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

docs/asciidoctor-reveal.js-master/package.json

@@ -46,7 +46,7 @@
   "homepage": "https://github.com/asciidoctor/asciidoctor-reveal.js",
   "dependencies": {
     "@asciidoctor/cli": "^3.1.0",
-    "reveal.js": "3.9.2"
+    "reveal.js": "4.3.0"
   },
   "devDependencies": {
     "@asciidoctor/core": "^2.1.1",