bugfix: trim specific characters in Kernel version

[HusterWan]

Signed-off-by: Michael Wan zirenwan@gmail.com

Ⅰ. Describe what this PR did

trim specific characters in Kernel version

Ⅱ. Does this pull request fix one issue?

fixes #2794

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

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[codecov]

Codecov Report

Merging #2796 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #2796      +/-   ##
=========================================
+ Coverage   69.27%   69.3%   +0.02%     
=========================================
  Files         277     277              
  Lines       17313   17313              
=========================================
+ Hits        11994   11999       +5     
+ Misses       3976    3973       -3     
+ Partials     1343    1341       -2

Flag	Coverage Δ
#criv1alpha2_test	39.35% <100%> (-0.04%)	⬇️
#integration_test_0	36.55% <100%> (+0.02%)	⬆️
#integration_test_1	35.39% <100%> (+0.03%)	⬆️
#integration_test_2	36.39% <100%> (ø)	⬆️
#integration_test_3	35.39% <100%> (-0.03%)	⬇️
#node_e2e_test	35.06% <100%> (+0.04%)	⬆️
#unittest	28.67% <100%> (ø)	⬆️

Impacted Files	Coverage Δ
pkg/kernel/kernel.go	80.95% <100%> (ø)	⬆️
daemon/mgr/container_utils.go	82.38% <0%> (+0.56%)	⬆️
ctrd/container.go	54.68% <0%> (+0.76%)	⬆️

[fuweid]

LGTM