[1.0.1 -> main] P2P: syncing fix

[heifner]

Two small P2P syncing fixes:

• Do not request next range of blocks if sync_last_requested_num is 0 as that case is handled in the first part of the if. If we do request a new range, request from a potentially different peer. Noticed that in practice it would often stick to its current peer here as this would be the first time it realized it needs a new range of blocks.
• Update sync_active_time when a block is received. Noticed this "timer" was firing simply because it was taking too long to apply the blocks. I was testing with sync-fetch-span of 5000.
• Normalize on using steady_clock for stopwatch functionality.

Merges release/1.0 into main including #671

Resolves #670

[ericpassmore]

Note:start
category: Other
component: Plugins/Cleos/Utils
summary: Peer syncing fixes to improve active sync time, better normalizer timer, and skip unneeded request for additional blocks.
Note:end