[Build]: Fix gmock not found issue in debian stretch slave container

[xumia]

Why I did it

Fix the gmock not found issue in debian stretch slave container.
Some of platforms, such as naphos, innovium, have such issue.

See https://dev.azure.com/mssonic/build/_build/results?buildId=62861&view=logs&j=1111c693-39b7-5a16-3aee-406c790b3886&t=d6851b2d-8b22-5ce8-7267-f54b7a47081b

2022-01-03T09:03:27.8890266Z /usr/bin/ld: cannot find -lgmock
2022-01-03T09:03:27.8891526Z /usr/bin/ld: cannot find -lgmock_main
2022-01-03T09:03:27.8892509Z collect2: error: ld returned 1 exit status
2022-01-03T09:03:27.8893983Z Makefile:467: recipe for target 'tests' failed
2022-01-03T09:03:27.8895220Z make[4]: *** [tests] Error 1
2022-01-03T09:03:27.8896751Z make[4]: Leaving directory '/sonic/src/sonic-swss-common/tests'
2022-01-03T09:03:27.8898681Z Makefile:439: recipe for target 'all-recursive' failed
2022-01-03T09:03:27.8900527Z make[3]: *** [all-recursive] Error 1
2022-01-03T09:03:27.8901915Z make[3]: Leaving directory '/sonic/src/sonic-swss-common'
2022-01-03T09:03:27.8903525Z Makefile:371: recipe for target 'all' failed
2022-01-03T09:03:27.8904463Z make[2]: *** [all] Error 2
2022-01-03T09:03:27.8905338Z make[2]: Leaving directory '/sonic/src/sonic-swss-common'
2022-01-03T09:03:27.8910445Z dh_auto_build: make -j4 returned exit code 2

How I did it

How to verify it

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106

Description for the changelog

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

[qiluo-msft]

stretch-backports

This option will impact all the packages in the same command line.

[xumia]

Thanks, we should add a new command to install the backport package.