bugfix: sort mounts according to the depth of destination path

[YaoZengzeng]

Ⅰ. Describe what this PR did

sortMounts sorts an array of mounts in lexicographic order.

This ensure that when mounting, the mounts don't shadow other mounts.

For example, if mounting /etc and /etc/resolv.conf, /etc/resolv.conf must not be mounted first.

Ⅱ. Does this pull request fix one issue?

ref: containerd/containerd#2596

Ⅲ. Why don't you add test cases (unit test/integration test)? (你真的觉得不需要加测试吗？)

Added

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[fuweid]

LGTM

[fuweid]

wait for CI

[codecov-io]

Codecov Report

Merging #2200 into master will increase coverage by 13.01%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           master    #2200       +/-   ##
===========================================
+ Coverage   51.94%   64.95%   +13.01%     
===========================================
  Files         208      208               
  Lines       16734    16743        +9     
===========================================
+ Hits         8693    10876     +2183     
+ Misses       7019     4514     -2505     
- Partials     1022     1353      +331

Flag	Coverage Δ
#criv1alpha1test	32.96% <100%> (?)
#criv1alpha2test	33.47% <100%> (?)
#integrationtest	39.93% <100%> (-0.04%)	⬇️
#unittest	23.99% <90%> (+0.04%)	⬆️

Impacted Files	Coverage Δ
daemon/mgr/spec_mount.go	79.43% <100%> (+10.05%)	⬆️
apis/server/utils.go	61.9% <0%> (-4.77%)	⬇️
ctrd/image.go	77.19% <0%> (-1.76%)	⬇️
daemon/mgr/container_storage.go	50.93% <0%> (+0.46%)	⬆️
pkg/utils/utils.go	84.3% <0%> (+0.58%)	⬆️
ctrd/container.go	53.82% <0%> (+0.95%)	⬆️
daemon/mgr/container.go	56.55% <0%> (+2.66%)	⬆️
daemon/mgr/container_types.go	83.63% <0%> (+2.72%)	⬆️
daemon/config/config.go	45.83% <0%> (+2.77%)	⬆️
daemon/mgr/container_utils.go	84.33% <0%> (+3.01%)	⬆️
... and 39 more