npm-run: add Spanish translation

[X] The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
[X] The page(s) have at most 8 examples.
[X] The page description(s) have links to documentation or a homepage.
[X] The page(s) follow the content guidelines.
[X] The page(s) follow the style guide.
[X] The PR title conforms to the recommended templates.
Version of the command being documented (if known):

tldr-pages / tldr