ATC build system: aarch64 support

[zrhoffman]

This PR

• Replaces cases where the build architecture is hard-coded as x86_64 with code that checks what the CPU architecture is
• Replaces build code using uname -a with rpm --eval %_arch. This is especially useful for M1 macs, where uname -a returns arm64 but rpm --eval %_arch returns aarch64 (which is correct for RPMs).
• Makes Traffic Router noarch architecture, since it's compiled to JVM bytecode

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Which Traffic Control components are affected by this PR?

• CDN in a Box
• T3C integration tests ATS RPM builder
• ATC Build system - Traffic Control Cache Config (t3c, formerly ORT), Traffic Control Health Client (tc-health-client), Traffic Monitor, Traffic Ops, Traffic Portal, Traffic Router, Traffic Stats, Grove, and Grove TC Config
  • Traffic Control Cache Config (t3c, formerly ORT)
  • Traffic Control Health Client (tc-health-client)
  • Traffic Monitor
  • Traffic Ops
  • Traffic Portal
  • Traffic Router
  • Traffic Stats
  • Grove and Grove TC Config

What is the best way to verify this PR?

Verify the RPMs build for your architecture:

cd infrastructure/cdn-in-a-box
make

PR submission checklist

• This PR affects tests
• This PR has documentation
• This PR has a CHANGELOG.md entry
• This PR DOES NOT FIX A SERIOUS SECURITY VULNERABILITY (see the Apache Software Foundation's security guidelines for details)

[zrhoffman]

Rebased so TR Ultimate Test Harness passes now that #7175 is merged

[ericholguin]

Was able to build on arm64 and get aarch64 rpms