Avoid container build by adding /.mariner-toolkit-ignore-dockerenv

[damonbarry]

Our Azure Linux builds started failing in the past week or so because Azure Linux recently made a change to how they detect container builds (see microsoft/azurelinux#11135), so the trick we employed to force a regular build (even though we're building in a container) stopped working. This change removes the trick and takes the recommended approach of adding /.mariner-toolkit-ignore-dockerenv to the container.

Other changes were also needed to resolve problems that came up while testing this PR:

• Snap builds began failing, seemingly due to a bad version combination of snapcraft and lxd. I updated the build task to do snap refresh before building.
• Our CI build for Azure Linux on arm64 uses the build scripts from the iot-identity-service repo, so I updated this repo's references to the iot-identity-service repo to fix the container build detection problem there.
• A recent update to a dependency of cross requires a newer rustc version and was causing the edgelet CI runs to fail in this PR because our rustc version is fixed at 1.73, I added the '--locked' flag to the cargo command that installs cross in the edgelet CI build.

To test, I confirmed that the CI Build passes with these changes.

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• Pull request includes test coverage for the included changes.
• Description of the pull request includes
  • concise summary of tests added/modified
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