Support Custom Events in azuremonitorexporter

[MatteoMeil]

Component(s)

exporter/azuremonitor

Is your feature request related to a problem? Please describe.

For consistency with azure-monitor-opentelemetry-exporter, azuremonitorexporter should support generating Microsoft.ApplicationInsights.Event (Custom Events on Application Insights)

Describe the solution you'd like

Event telemetry should be generated from logs using APPLICATION_INSIGHTS_EVENT_MARKER_ATTRIBUTE attribute value as discriminator (reference code)

Describe alternatives you've considered

No response

Additional context

No response

[github-actions]

Pinging code owners:

• exporter/azuremonitor: @pcwiese

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[atoulme]

@pcwiese @hgaol please review as codeowners.