Renames application insights keys to be more clear (#587)

* renames `telemetry_key` to `microsoft_telemetry_key`
* renames `instrumentation_key` to `instance_telemetry_key`
* renames `can_share` to `can_share_with_microsoft`
* renames the `applicationinsights-rs` instances to `internal` and `microsoft` respective of the keys used during construction.

This clarifies the underlying use of Application Insights keys and uses struct tuple to ensure the keys are used correctly via rust's type checker.

src/agent/onefuzz-agent/src/local/common.rs

@@ -166,13 +166,11 @@ pub fn build_common_config(args: &ArgMatches<'_>) -> Result<CommonConfig> {
     };
 
     let config = CommonConfig {
-        heartbeat_queue: None,
-        instrumentation_key: None,
-        telemetry_key: None,
         job_id,
         task_id,
         instance_id,
         setup_dir,
+        ..Default::default()
     };
     Ok(config)
 }