update debug dependency to 4.3.2 ( Memory Leak )

[maximegheraille]

Hi,

We have seen this vulnerability for the dependency debug@4.3.1 with a CVSS score of 7.5.
NPM debug prior to 4.3.0 has a Memory Leak when creating debug instances inside a function which can have a significant impact in the Availability. This happens since the function debug in the file src/common.js does not free up used memory.

To resolve this issue we need to upgrade to version debug@4.3.2 which will resolve the vulnerability.

I see that there is an open PR to upgrade the dependency #201, is there a reason is has been open for so long not yet merged?