address issues related to third-party library: proc-maps

[bmc-msft]

We use proc-maps in the agent code, which appears to be unmaintained, with at least one PR open 2019 (see rbspy/proc-maps#5).

While functional, proc-maps pulls in failure which is deprecated (see rust-lang-deprecated/failure#347) and has a type confusion bug (see rust-lang-deprecated/failure#336).

At a minimum, we should submit updates to proc-maps and try to work with the author to get them included. There are other alternatives, such as procmaps, though not as featureful.

AB#39994651

[ranweiler]

The proc-maps crate is a dependency of the actively-maintained rbspy, and belongs to the org for that project. I think it has been neglected because what it does is really, really simple. Our usage is even more minimal, so we should maybe just replace this with our own minimal procfs parser.

[bmc-msft]

The procmaps project I linked is extremely simple alternative.

[Porges]

failure is no longer imported by any dependency path (see #2285 which removes the cargo audit suppression). proc-maps has been updated last year and this year, so I think we can close this.