Drop technical requirements for all team members

[jameshochadel]

Changes proposed in this pull request:

Team members without technical or compliance roles do not need to review technical documentation. They also may not have contingency plan roles.

Questions for @pburkholder and friends:

• Is it safe to totally drop the CP requirement, or is it possible that non-(compliance, engineering) team members will have a CP role? For instance, the director.
• Do non-technical team members need GitHub access at all? If not, we can remove the step in which they're added to the organization.
• Is IR training required of all team members? (I'm assuming nonpublic information still is.)
• I left "read security policies and procedures" in, since business unit may be subject to some controls. Is that right?
• I left "read delivery process" in, but I'm not sure other teams (biz, program, eventually outreach?) use GitHub to track their work, so is it necessary for all team members to read?

security considerations

We must ensure that changes to this onboarding are in line with our practices as detailed in our SSP.