Revert "fix: bump release-please from 15.13.0 to 16.1.0"

[chingor13]

Reverts google-github-actions/release-please-action#845

The action can't build the single js file via ncc with the newest version of release-please

ncc: Version 0.38.1
ncc: Compiling file index.js into CJS
Error: Module parse failed: Unexpected token (26:23)
File was processed with these loaders:
 * ./node_modules/@vercel/ncc/dist/ncc/loaders/empty-loader.js
 * ./node_modules/@vercel/ncc/dist/ncc/loaders/relocate-loader.js
 * ./node_modules/@vercel/ncc/dist/ncc/loaders/shebang-loader.js
You may need an additional loader to handle the result of these loaders.
|     npm_lifecycle_event: event,
|     npm_lifecycle_script: cmd,
>     __webpack_require__.ab + "node-gyp.js",
|   })
| 
    at /home/chingor/code/release-please-action/node_modules/@vercel/ncc/dist/ncc/index.js.cache.js:38:1896272
    at /home/chingor/code/release-please-action/node_modules/@vercel/ncc/dist/ncc/index.js.cache.js:38:396262
    at _done (eval at create (/home/chingor/code/release-please-action/node_modules/@vercel/ncc/dist/ncc/index.js.cache.js:21:75523), <anonymous>:9:1)
    at eval (eval at create (/home/chingor/code/release-please-action/node_modules/@vercel/ncc/dist/ncc/index.js.cache.js:21:75523), <anonymous>:34:22)