[Mempool] Don't log times that are <= 0 for insertion time to block timestamp

[bchocho]

Description

This happens due to retry/duplication and should be ignored (instead of logging time 0). This cleans up the metric a bit, especially for forge tests that have enough latency that causes frequent transaction retries.

Test Plan

[github-actions]

✅ Forge suite compat success on aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7

Compatibility test results for aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7 (PR)
1. Check liveness of validators at old version: aptos-node-v1.5.1
compatibility::simple-validator-upgrade::liveness-check : committed: 3133 txn/s, latency: 6932 ms, (p50: 6000 ms, p90: 10500 ms, p99: 21800 ms), latency samples: 191140
2. Upgrading first Validator to new version: 7459a31822918991025fc647dcf1e8686a339fb7
compatibility::simple-validator-upgrade::single-validator-upgrade : committed: 1781 txn/s, latency: 16211 ms, (p50: 19000 ms, p90: 22100 ms, p99: 22500 ms), latency samples: 92640
3. Upgrading rest of first batch to new version: 7459a31822918991025fc647dcf1e8686a339fb7
compatibility::simple-validator-upgrade::half-validator-upgrade : committed: 1853 txn/s, latency: 15671 ms, (p50: 18700 ms, p90: 22000 ms, p99: 22400 ms), latency samples: 92680
4. upgrading second batch to new version: 7459a31822918991025fc647dcf1e8686a339fb7
compatibility::simple-validator-upgrade::rest-validator-upgrade : committed: 2264 txn/s, latency: 9948 ms, (p50: 10100 ms, p90: 13800 ms, p99: 15400 ms), latency samples: 140400
5. check swarm health
Compatibility test for aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7 passed
Test Ok

• Grafana dashboard
• Humio Logs
• Test runner output
• Test run is land-blocking

[github-actions]

✅ Forge suite framework_upgrade success on aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7

Compatibility test results for aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7 (PR)
Upgrade the nodes to version: 7459a31822918991025fc647dcf1e8686a339fb7
framework_upgrade::framework-upgrade::full-framework-upgrade : committed: 3989 txn/s, latency: 7526 ms, (p50: 7200 ms, p90: 10500 ms, p99: 20200 ms), latency samples: 163560
5. check swarm health
Compatibility test for aptos-node-v1.5.1 ==> 7459a31822918991025fc647dcf1e8686a339fb7 passed
Test Ok

• Grafana dashboard
• Humio Logs
• Test runner output
• Test run is land-blocking

[github-actions]

✅ Forge suite realistic_env_max_load success on 7459a31822918991025fc647dcf1e8686a339fb7

two traffics test: inner traffic : committed: 6955 txn/s, latency: 5635 ms, (p50: 5400 ms, p90: 6900 ms, p99: 11100 ms), latency samples: 3004740
two traffics test : committed: 100 txn/s, latency: 3027 ms, (p50: 3000 ms, p90: 3800 ms, p99: 5400 ms), latency samples: 1760
Max round gap was 1 [limit 4] at version 1374602. Max no progress secs was 4.050201 [limit 10] at version 1374602.
Test Ok

• Grafana dashboard
• Humio Logs
• Test runner output
• Test run is land-blocking