Refactor/ornl-pip-ci

[RamonAra209]

• Created a ornl ci configuration for pip on Summit
• Modified SDK_WORK_DIR to reflect ORNL standard
• Forced usage of python 3.8.10

[mtitov]

@RamonAra209 we don't have Summit runners yet (will take some time to figure out how to configure that), let's switch from Summit to Ascent:

• remove Summit jobs, but keep .on_summit
• add Ascent machine
• rework PIP_WORK_DIR handling - remove it from global variables, and keep it per machine definition

.on_ascent:
  variables:
    SITE: "ascent"
    VENV_ENV_NAME: "ascent-env"
    PIP_WORK_DIR: ${SDK_WORK_DIR_OPEN}/pip

.on_summit:
  variables:
    SITE: "summit"
    VENV_ENV_NAME: "summit-env"
    PIP_WORK_DIR: ${SDK_WORK_DIR_ALPINE}/pip

and we will have a cleanup per machine here, since all these machines use different FSs p.s. also I've added a line from Misha's PR https://github.com/ExaWorks/SDK/pull/208 (recreate corresponding directory every 5 days)

.pip_cleanup:
  stage: cleanup
  when: always
  script:
   - find ${PIP_WORK_DIR} -maxdepth 0 -type d -ctime +5 | xargs rm -rf
   - *finalize

.....

pip_cleanup_ascent:
  variables:
    RUNNER_TYPE: "nobatch"
  extends: [ .on_ascent, .job_tags, .pip_cleanup ]