seems to be related to an invalid version of github.com/kr/pretty@v0.3.0

$ go get github.com/gin-gonic/gin
go get: github.com/gin-gonic/gin@v1.7.7 updating to
        github.com/gin-gonic/gin@v1.8.0 requires
        github.com/go-playground/validator/v10@v10.10.0 requires
        github.com/kr/pretty@v0.3.0: reading github.com/kr/pretty/go.mod at revision v0.3.0: unknown revision v0.3.0

Comment From: appleboy

try

go get github.com/gin-gonic/gin@v1.8.1