config file log level affects `teleport` command verbosity

[GavinFrazar]

We should add a --debug flag to teleport, and for commands that don't start a daemon it should ignore the log level in config file.

Expected behavior:

If I run a command like teleport discovery bootstrap -c /etc/teleport.yaml and I get an error message, I expect to see a normal error message format instead of debug level format.

Example expected output:

$ teleport discovery bootstrap -c ~/code/dev/clusters/alpha/agent.yaml --manual
Reading configuration at "/Users/gavin/code/dev/clusters/alpha/agent.yaml"...
ERROR: discovery service type does not support "ec2x", supported resource types are: [ec2 eks rds rdsproxy redshift redshift-serverless elasticache memorydb opensearch docdb]

Current behavior:

If a teleport yaml config file has log level set to DEBUG, then the command that acts on the config file will also use DEBUG level, and error messages are formatted for debug mode:

---
version: v3
teleport:
  nodename: "mbp"
  log:
    severity: "DEBUG"

Example unexpected output:

$ teleport discovery bootstrap -c ~/code/dev/clusters/alpha/agent.yaml --manual
Reading configuration at "/Users/gavin/code/dev/clusters/alpha/agent.yaml"...

ERROR REPORT:
Original Error: *trace.BadParameterError discovery service type does not support "ec2x", supported resource types are: [ec2 eks rds rdsproxy redshift redshift-serverless elasticache memorydb opensearch docdb]
Stack Trace:
    github.com/gravitational/teleport/api/types/matchers_aws.go:116 github.com/gravitational/teleport/api/types.(*AWSMatcher).CheckAndSetDefaults
    github.com/gravitational/teleport/lib/config/configuration.go:1597 github.com/gravitational/teleport/lib/config.applyDiscoveryConfig
    github.com/gravitational/teleport/lib/config/configuration.go:664 github.com/gravitational/teleport/lib/config.ApplyFileConfig
    github.com/gravitational/teleport/lib/configurators/configuratorbuilder/builder.go:38 github.com/gravitational/teleport/lib/configurators/configuratorbuilder.BuildConfigurators
    github.com/gravitational/teleport/tool/teleport/common/configurator.go:144 github.com/gravitational/teleport/tool/teleport/common.onConfigureDiscoveryBootstrap
    github.com/gravitational/teleport/tool/teleport/common/teleport.go:685 github.com/gravitational/teleport/tool/teleport/common.Run
    github.com/gravitational/teleport/e/tool/teleport/main.go:19 main.main
    runtime/proc.go:271 runtime.main
    runtime/asm_arm64.s:1222 runtime.goexit
User Message: discovery service type does not support "ec2x", supported resource types are: [ec2 eks rds rdsproxy redshift redshift-serverless elasticache memorydb opensearch docdb]

Bug details:

• Teleport version: v16
• Recreation steps: use the same command from my example, and misconfigure the discovery_service section in some way to trigger an error. I used an invalid matcher type:

  discovery_service:
  enabled: true
  discovery_group: "teleport-dev-2"
  aws:
  - types:
      - "ec2x"

[webvictim]

tctl does the same thing, which results in a few lines of surplus output with every command.