chore(deps): update dependency superagent to v6

[mend-for-github-com[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
superagent	^5.3.1 -> ^6.0.0

By merging this PR, the below issues will be automatically resolved and closed:

Severity	CVSS Score	CVE	GitHub Issue
High	7.5	CVE-2022-24999	#802

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Release Notes

ladjs/superagent

### [`v6.0.0`](https://togithub.com/ladjs/superagent/releases/tag/v6.0.0) [Compare Source](https://togithub.com/ladjs/superagent/compare/v5.3.1...v6.0.0) - fix: bump deps, fixed linting, specific retry approach [`d68907b`](https://togithub.com/ladjs/superagent/commit/d68907b) - fix: fixed content-type case-sensitivity (closes [#​1572](https://togithub.com/ladjs/superagent/issues/1572)) [`44fadf9`](https://togithub.com/ladjs/superagent/commit/44fadf9) - Add mention of bearer auth to docs ([#​1583](https://togithub.com/ladjs/superagent/issues/1583)) [`e88a13f`](https://togithub.com/ladjs/superagent/commit/e88a13f) - Update jQuery in tail.html ([#​1582](https://togithub.com/ladjs/superagent/issues/1582)) [`a009ace`](https://togithub.com/ladjs/superagent/commit/a009ace) - Revert "Improve .retry() method functionality with delays and prevent calling on successful request ([#​1527](https://togithub.com/ladjs/superagent/issues/1527))" [`74641bb`](https://togithub.com/ladjs/superagent/commit/74641bb) - fix: fixed lint, yarnlock [`0c4f96f`](https://togithub.com/ladjs/superagent/commit/0c4f96f) - Improve .retry() method functionality with delays and prevent calling on successful request ([#​1527](https://togithub.com/ladjs/superagent/issues/1527)) [`62eae78`](https://togithub.com/ladjs/superagent/commit/62eae78) - fix: fixed travis [`f8ea331`](https://togithub.com/ladjs/superagent/commit/f8ea331) - removed extra should from test description ([#​1581](https://togithub.com/ladjs/superagent/issues/1581)) [`cc34638`](https://togithub.com/ladjs/superagent/commit/cc34638)

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