feat: add C implementation for stats/base/dists/exponential/mode

[sethdivyansh]

Resolves #3588

Description

• adds C implementation for @stdlib/stats/base/dists/exponential/mode along with relevant tests, benchmarks and examples

This pull request:

• progresses: [RFC]: Add C implementation for @stdlib/stats/base/dists/exponential/mode #3588

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

---

@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/exponential/mode	$\color{green}161/161$ $\color{green}+100.00\%$	$\color{green}8/8$ $\color{green}+100.00\%$	$\color{green}2/2$ $\color{green}+100.00\%$	$\color{green}161/161$ $\color{green}+100.00\%$

The above coverage report was generated for the changes in this PR.

[Planeshifter]

Meanwhile, a PR for this issue has already been merged. Thanks for filing a PR either way!