Introduce Sentry.capture_log

[solnic]

First step towards Structured Logging #2600

This adds Sentry.capture_log interface with a new underlying LogEvent event type.

Closes #2603

[AbhiPrasad]

Looks solid! Just one comment about the client method, and then we are good to ✅

Before we move on to the logger interface though (#2604), can we spec out a buffering implementation for logs? We can do it after this PR and create another issue to track it so that we contain the scope of this particular set of changes.

https://develop.sentry.dev/sdk/telemetry/logs/#implementation

It would be nice to get a lightweight logs buffer so that we don't overwhelm sentry with requests, logs were designed so you can send multiple log payloads in a single log envelope.

[solnic]

Before we move on to the logger interface though (#2604), can we spec out a buffering implementation for logs?

@AbhiPrasad yes this makes sense, I reported #2613 :)

[solnic]

@AbhiPrasad I added remaining pieces of info to the attributes, please take another look 😄

[AbhiPrasad]

One change with server_name, but approving to unblock! Thanks for the quick pace on this.