Simplify and update quality Intermediate career development

Why is this change being made?

This MR is part of https://gitlab.com/gitlab-org/quality/team-tasks/-/issues/714

This removes Quality specific sections under Leadership and Values since we align with the Engineering section.

Also , refactored the Technical competencies section so its more in sync with our job matrix/ career matrix worksheet template:

• Quality Engineering Job Matrix - https://docs.google.com/spreadsheets/d/1DNJdI-LXSsEFQvLSBhIrU273sH9LiDftK6CBdGd80mE/edit?usp=sharing
• [TEMPLATE] Career Matrix Level Worksheet for Software Engineer in Test - Intermediate - v2 2020 Iteration - https://docs.google.com/spreadsheets/d/1Y1mfyqfQyTgcn36UfWZrvdy5tqjzwTfEp1EJrlZI0nY/edit?usp=sharing

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
• Assign this change to the correct DRI
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the "Maintained by" section in on the page being edited.
  • If your manager does not have merge rights, please ask someone to merge it AFTER it has been approved by your manager in #mr-buddies.
  • If the changes relate to any part of the project other than updates to content and/or data files please make sure to ping @gl-static-site-editor in a comment for a review and merge. For example changes to .gitlab-ci.yml, JavaScript/CSS/Ruby code or the layout files. (this requirement has been removed pending identification of a new DRI for the handbook)