Backport of snapshot: some improvments to the snapshot process into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #17236 to be assessed for backporting due to the inclusion of the label backport/1.15.

The below text is copied from the body of the original PR.

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Description

snapshot: some improvments to the snapshot process

• Add raft to the snapshot logger because the log messages are from raft package, making it consistent with other snapshot logs like starting snapshot up to, which are from the raft package as well. Also it allows users know where to search for the logger message

// before
2023-05-08T10:10:19.954-0400 [INFO]  agent.server.raft: starting snapshot up to: index=30
2023-05-08T10:10:19.954-0400 [INFO]  agent.server.snapshot: creating new snapshot: path=/tmp/dc-2-consul-server-1/raft/snapshots/3-30-1683555019954.tmp
2023-05-08T10:10:19.967-0400 [INFO]  agent.server.raft: snapshot complete up to: index=30

// after
2023-05-08T10:04:20.361-0400 [INFO]  agent.server.raft: starting snapshot up to: index=25
2023-05-08T10:04:20.361-0400 [INFO]  agent.server.raft.snapshot: creating new snapshot: path=/tmp/dc-2-consul-server-1/raft/snapshots/2-25-1683554660361.tmp
2023-05-08T10:04:20.382-0400 [INFO]  agent.server.raft: snapshot complete up to: index=25
2023-05-08T10:04:20.382-0400 [INFO]  agent.server: creating temporary file of snapshot: path=/var/folders/c0/0_4qftyd47g8bkq_4_5dpw4m0000gn/T/snapshot3125735996

• Print out the path of the temp snapshot file for trouble shooting

• Update the doc a bit

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 99c3322 - 757f22b - 7eda9c7 - 8124fb3 - 164cada

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR