Increase check point state cache size to 10

[terencechain]

Previous size 4 was not enough given more forks than expected in current testnet.

# HELP check_point_state_cache_hit The number of check point state requests that are present in the cache.
check_point_state_cache_hit 133643
# HELP check_point_statecache_miss The number of check point state requests that aren't present in the cache.
check_point_statecache_miss 2762

Increased the 10:

# HELP committee_cache_hit The number of committee requests that are present in the cache.
committee_cache_hit 135609
# HELP committee_cache_miss The number of committee requests that aren't present in the cache.
committee_cache_miss 12

Improved hit ratio from 97.9% to 99.9%, it may not seem like a lot but that's a saving of 2000 extra hash tree root and epoch transition of a mainnet state

[codecov]

Codecov Report

Merging #4818 into master will increase coverage by 13.19%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master    #4818       +/-   ##
===========================================
+ Coverage   43.57%   56.77%   +13.19%     
===========================================
  Files         230      247       +17     
  Lines       17296    18263      +967     
===========================================
+ Hits         7537    10369     +2832     
+ Misses       8547     6431     -2116     
- Partials     1212     1463      +251