Bump acorn and @ampproject/rollup-plugin-closure-compiler#4

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dependabot/npm_and_yarn/acorn-and-ampproject/rollup-plugin-closure-compiler-7.3.1branson2015/Spindle:dependabot/npm_and_yarn/acorn-and-ampproject/rollup-plugin-closure-compiler-7.3.1Copy head branch name to clipboard