release-24.2: peer: fix redaction of peer (re-)connects

[blathers-crl]

Backport 1/1 commits from #133219 on behalf of @nicktrav.

/cc @cockroachdb/release

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Currently, when logging the connection or reconnection of a peer, the log is line fully redacted. This impedes diagnosing network issues.

Fix the redaction by printing a SafeString into the buffer, rather than a raw string, which is marked as unsafe by default.

Fix #133218.

Release note: None.

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Release justification: Low risk obs change.

[blathers-crl]

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[blathers-crl]

It looks like your PR touches production code but doesn't add or edit any test code. Did you consider adding tests to your PR?

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