More updates for the current OTel (OpenTelemetry) conventions

[iinuwa]

Proposed Changes

Update to latest OTel conventions

• Swap order of queue name and operation name in Activity name
• Add messaging.operation.name tag

Builds on #1716.
Fixes #1715.

In order to get 7.0 released, this can wait until 7.1.

Types of Changes

What types of changes does your code introduce to this project?

• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)

Checklist

• I have read the CONTRIBUTING.md document
• I have signed the CA (see https://cla.pivotal.io/sign/rabbitmq)
• All tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in related repositories

Further Comments

Regarding #1715 (comment), I used fetch instead of polling fetch or basic.get because:

• It avoids using longer basic_ prefix.
• It remains consistent with a single verb for all operation names.
• The word "polling" (to me) implies that the operation is repeated multiple times, but this activity is fired on a single instance of the basic.get. fetch (in my mind) conveys a pull operation to me and is meaningfully distinguished from deliver.

[michaelklishin]

@iinuwa should we close #1716 then? Is this meant to address the feedback there?