Add metrics to track rejected writes during ingest

[hiltontj]

Follows #25689

Problem statement

#25692 added metrics to track successful ingest per database, however, we do not have any metrics to track unsuccessful ingest.

Proposed solution

As per #25692 (comment), we should add a influxdb_write_lines_rejected_total metric that tracks the number of lines rejected.

Alternatives considered

N/A

Additional context

N/A