[receiver/snmpreceiver] Add support for SNMP objects of type counter64

[technimad-splunk]

Description:
Add support for SNMP obecjts of type counter64. The gosnmp library already has support for this type.
And we already cast all numerical values to an int64.

Link to tracking Issue: #23897

Testing: Started the collector. No startup or runtime errors percieved.
I didn't have a SNMP target with counter64 support.
I'm relying on the gosnmp library to have tested interoperability.

Documentation: n/a

[Scrappy79]

@technimad-splunk, looks like the error is still ongoing with the latest contrib version (0.84.0):

Error scraping metrics {"kind": "receiver", "name": "XXXXX", "data_type": "metrics", "error": "problem with getting indexed data: data for OID '.1.3.6.1.2.1.31.1.1.1.6.1' not a supported type

  hw.network.io:
    description: Received and transmitted network traffic
    unit: By
    sum:
      aggregation: cumulative
      monotonic: true
      value_type: int
    column_oids:
      - oid: ".1.3.6.1.2.1.31.1.1.1.6"
        attributes:
          - name: hw.network.interface.descr

[technimad-splunk]

Hi @Scrappy79, thanks for sharing.
I've found the issue. Data of a Counter64 is returned as a uint64, which isn't handled at the moment.
I will submit a new PR to fix this.

[Scrappy79]

Thanks @technimad-splunk, much appreciated.