Feature: Implement delete issue link api

[ahmadsalimi]

Description

Implementation of #309

API:

DELETE rest/api/2/issueLink/{linkId}

Information that is useful here:

• The What: Calls delete issue link API
• Type of change: New feature
• Breaking change: Yes
• Related to an issue: Yes, Add API call to delete an issue link #309
• Jira Version + Type: Jira REST API v2

Example:

// Example code
resp, err := testClient.Issue.DeleteLink("10054")

Checklist

• Unit or Integration tests added
  • Good Path
  • Error Path
• Commits follow conventions described here:
  • Conventional Commits 1.0.0
  • The seven rules of a great Git commit message
• Commits are squashed such that
  • There is 1 commit per isolated change
• I've not made extraneous commits/changes that are unrelated to my change.

[benjivesterby]

This looks good to me. Once at least one of the other maintainers gives the 👍 we can merge. If nobody else reviews by the end of next week I'll merge it in.

[andygrunwald]

LGTM

[andygrunwald]

Thanks @ahmadsalimi