Bump json5 and rollup-plugin-postcss in /x/webapp-demo#15

dependabot[bot] wants to merge 1 commit intomasternomasters/hashmap:masterfrom

dependabot/npm_and_yarn/x/webapp-demo/json5-and-rollup-plugin-postcss--removednomasters/hashmap:dependabot/npm_and_yarn/x/webapp-demo/json5-and-rollup-plugin-postcss--removedCopy head branch name to clipboard