Remove indirect dependency on github.com/pkg/errors

[cbandy]

The github.com/pkg/errors package has been archived for some time.

--- go mod graph # release-2.0
+++ go mod graph # pr-42
@@ -1,11 +1,8 @@
 gomodules.xyz/jsonpatch/v2 github.com/davecgh/[email protected]
-gomodules.xyz/jsonpatch/v2 github.com/evanphx/[email protected]
-gomodules.xyz/jsonpatch/v2 github.com/pkg/[email protected]
 gomodules.xyz/jsonpatch/v2 github.com/pmezard/[email protected]
 gomodules.xyz/jsonpatch/v2 github.com/stretchr/[email protected]
 gomodules.xyz/jsonpatch/v2 [email protected]
-github.com/evanphx/[email protected] github.com/jessevdk/[email protected]
-github.com/evanphx/[email protected] github.com/pkg/[email protected]
+gomodules.xyz/jsonpatch/v2 gopkg.in/evanphx/[email protected]
 github.com/stretchr/[email protected] github.com/davecgh/[email protected]
 github.com/stretchr/[email protected] github.com/pmezard/[email protected]
 github.com/stretchr/[email protected] github.com/stretchr/[email protected]

[CLAassistant]

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