cli/command/image: add go:build tag to prevent downgrading go version

[thaJeztah]

• using the check from implement module compatibility check #4723

Before this:

make shell
make -C ./internal/gocompat/
...

GO111MODULE=on go test -v
# github.com/docker/cli/cli/command/image
../../cli/command/image/push.go:177:62: predeclared any requires go1.18 or later (-lang was set to go1.16; check go.mod)
FAIL	gocompat [build failed]
make: *** [Makefile:3: verify] Error 1
make: Leaving directory '/go/src/github.com/docker/cli/internal/gocompat'

After this patch:

make shell
make -C ./internal/gocompat/
...

GO111MODULE=on go test -v
=== RUN   TestModuleCompatibllity
    main_test.go:133: all packages have the correct go version specified through //go:build
--- PASS: TestModuleCompatibllity (0.00s)
PASS
ok  	gocompat	0.007s
make: Leaving directory '/go/src/github.com/docker/cli/internal/gocompat'

- Description for the changelog

Fix a compile error when using the CLI code as a go module

- A picture of a cute animal (not mandatory but encouraged)

[glours]

LGTM

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 61.75%. Comparing base (6904185) to head (1fd8e24).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5162      +/-   ##
==========================================
- Coverage   61.76%   61.75%   -0.01%     
==========================================
  Files         297      297              
  Lines       20768    20768              
==========================================
- Hits        12828    12826       -2     
- Misses       7024     7025       +1     
- Partials      916      917       +1