Switch to oapi-codegen/v2

[miquella]

Description

Importing the module is causing issues with a transitive dependency:

ambiguous import: found package github.com/ugorji/go/codec in multiple modules:
	github.com/ugorji/go v1.1.4 (…)
	github.com/ugorji/go/codec v1.2.11 (…)

This issue was reported upstream as oapi-codegen/oapi-codegen#1308 and was fixed in oapi-codegen/oapi-codegen#1310. This fixes the issue as it removes the transitive dependency that was requiring codec (github.com/go-gonic/gin).

Switching to v2 also addresses oapi-codegen/oapi-codegen#1142, superseding much of the need for #11 and #12.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Ran the golang.org/x/exp/cmd/gorelease tool to ensure no API compatibility issues could be found.

Checklist (check all applicable):

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard to understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes