[v1.x] Port #20864 from v1.9.x

[josephevans]

Fix pip installation in containers (#20864)

• Fix pip install inside docker.

• Update ci/docker/install/centos7_python.sh

Co-authored-by: bgawrych bartlomiej.gawrych@intel.com

• Update ci/docker/install/ubuntu_python.sh

Co-authored-by: bgawrych bartlomiej.gawrych@intel.com

Co-authored-by: bgawrych bartlomiej.gawrych@intel.com

Description

(Brief description on what this PR is about)

Checklist

Essentials

• PR's title starts with a category (e.g. [BUGFIX], [MODEL], [TUTORIAL], [FEATURE], [DOC], etc)
• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage
• Code is well-documented

Changes

• Feature1, tests, (and when applicable, API doc)
• Feature2, tests, (and when applicable, API doc)

Comments

• If this change is a backward incompatible change, why must this change be made.
• Interesting edge cases to note here

[mxnet-bot]

Hey @josephevans , Thanks for submitting the PR
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[bgawrych]

@mxnet-bot run ci [unix-cpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-cpu]