There are several issues.
Firstly, you should never be able to see the coloured cable cores. It's not actually dangerous as the copper is still insulated, but the cable cores are not protected so they are at risk of being damaged. This is a breach of electrical regulations.
Secondly, the location of that filter is not ideal. I would never choose to put it that close to an electrical outlet of any sort. That said, the proximity isn't really a safety issue as a pipe dripping from a foot above will wet the electrical outlet just as easily as one dripping from an inch above. So if space is tight, I'd say that while it isn't ideal, it isn't really wrong as such.
The third issue is the leak. There absolutely should not be dripping water. The first job of a plumber or boiler installer is not to leave leaks so what you have is absolutely not to a reasonable standard and the installer is legally responsible to correct this.