fix(instrumentation): always process Git Operation spans

[jamietanna]

Changes

As part of #39596, we added the ability
to report the Git Operations Statistics at the end of the Renovate
run, by introducing a SpanProcessor.

However, this didn't correctly take into account the fact that this
would only be enabled if Renovate was configured to log/export traces,
which is not the case in most deployments.

As noted in #42118, this leads to a blank log line output, which isn't
very useful.

To correct this, we nede to always process these spans, even if tracing
is not enabled.

Context

Please select one of the below:

• This closes an existing Issue: Closes: "Git operations statistics" does not fire on Mend-hosted platforms #42118
• This doesn't close an Issue, but I accept the risk that this PR may be closed if maintainers disagree with its opening or implementation

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• Yes — other (please describe): Claude Sonnet 4.6

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