Bump rollup-plugin-terser from 6.1.0 to 7.0.0 (#259)

Bumps [rollup-plugin-terser](https://github.com/TrySound/rollup-plugin-terser) from 6.1.0 to 7.0.0.
- [Release notes](https://github.com/TrySound/rollup-plugin-terser/releases)
- [Commits](TrySound/rollup-plugin-terser@v6.1.0...v7.0.0)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -71,7 +71,7 @@
     "rollup": "^2.3.2",
     "rollup-plugin-babel": "^4.3.3",
     "rollup-plugin-serve": "^1.0.1",
-    "rollup-plugin-terser": "^6.0.0",
+    "rollup-plugin-terser": "^7.0.0",
     "rollup-plugin-typescript2": "^0.27.0",
     "sinon": "^9.0.1",
     "typescript": "^3.6.4"