[automate-2914] force-upgrade integration scenario: v1 -> v2 with migrated legacy policies

[bcmdarroch]

🔩 Description: What code changed, and why?

This PR adds integration testing for the following scenario:

1. deploys an older version of Automate using IAM v1 (this will be the case for any customer using Automate who has not upgraded to IAM v2)
2. upgrades Automate to the latest build, which force-upgrades the system to IAM v2

♻️ For the force-upgrade, we have removed the following v2-specific integration tests scripts:

• iam_v2_no_legacy_policies.sh
• iam_v2_upgrade_diagnostics.sh
• iam_v2_with_v1_policies.sh
• upgrade_reset_iam_v2.sh
• reset_admin_access_v2.sh

These scripts all used upgrade-to-v2 and reset-to-v1, commands which will be deprecated by the force-upgrade.

🎉 Now we have the following integration tests, all prefixed by iam:

• iam v1 to v2 force-upgrade
• iam v1 to v2 force-upgrade (diagnostics only)
• iam reset admin access
• iam automate-gateway integration
• iam v2 with legacy to v2 force-upgrade (coming soon! [automate-2917] v2 with legacy policies -> force-upgrade to latest v2 integration test #3008)
• iam v2 with no legacy to v2 force-upgrade (coming soon! [automate-2916] v2 with no legacy policies -> force-upgrade to latest v2 integration test #3009)
• iam v2 with no legacy to v2 force-upgrade (diagnostics only) (coming soon! [automate-2916] v2 with no legacy policies -> force-upgrade to latest v2 integration test #3009)

The inspec test suites have also been reorganized:

• a2-api-integration tests API behavior. This now includes all IAM v2 APIs. To distinguish from the iam inspec suites, these tests all assume admin-level access.
• a2-iam-v1-integration tests permissions on APIs specific to v1 (default policies)
• a2-iam-no-legacy-integration tests permissions on APIs on a fresh system without v1 legacy policies
• a2-iam-legacy-integration tests permissions on APIs on a system with v1 legacy policies

⛓️ Related Resources

follow-ups:
v2 force-upgrade to v2 with legacy policies: #3008
v2 force-upgrade to v2 with no legacy policies: #3009

👍 Definition of Done

• all buildkite tests are passing, except for the ones related to ingest permissions (to be fixed by Ingest access legacy migration #2987)

👟 How to Build and Test the Change

when you check out this branch and start in a fresh studio, you can mimic the force-upgrade integration scenario following these steps:

inspec:

start_all_services

# I've had to use this version of inspec to avoid a specific bug when running inspec locally
hab pkg install -b chef/inspec/4.18.51/20191211220937

inspec exec inspec/a2-iam-v1-integration

# rebuilding these services simulates the force-upgrade
rebuild components/automate-deployment && rebuild components/automate-gateway/ && rebuild components/authz-service/ && rebuild components/teams-service/ && rebuild components/automate-cli

# tests API behavior, given admin-level access
inspec exec inspec/a2-api-integration

# tests permissions, given v1 legacy policies
inspec exec inspec/a2-iam-legacy-integration

diagnostics:

build components/automate-cli
start_all_services

# this generates data on v1
chef-automate diagnostics run iam --skip-cleanup

# rebuilding these services simulates the force-upgrade
rebuild components/automate-deployment && rebuild components/automate-gateway/ && rebuild components/authz-service/ && rebuild components/teams-service/

# this verifies the data that was generated while on v1, 
# including v1 policies that have been migrated to v2 policies
chef-automate diagnostics run iam --skip-generate

✅ Checklist

• I have read the CONTRIBUTING document.
• Tests added/updated?
• Docs added/updated?
• All commits have been signed-off for the Developer Certification of Origin.