[Core] Investigate memory leaks, manual GC on ResetToGenesis - (Issue #440)

[deblasis]

Description

This PR reclaims memory manually after the memory-churn intensive operations performed during a ResetToGenesis debug command

In particular:

	// Clear the BlockStore
	if err := m.blockStore.ClearAll(); err != nil {
		return err
	}

	// Clear all the Trees
	if err := postgresCtx.clearAllTreeState(); err != nil {
		return err
	}

This is the result of my initial investigation #440 (comment)

Issue

This might fix #440 but I'd like another pair of eyes on this to understand if this is the right approach

Type of change

Please mark the relevant option(s):

• New feature, functionality or library
• Bug fix
• Code health or cleanup
• Major breaking change
• Documentation
• Other

List of changes

• Calling debug.FreeOSMemory() after cleaning up the persistence structures

Testing

• make develop_test
• LocalNet w/ all of the steps outlined in the README

Required Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have tested my changes using the available tooling
• I have updated the corresponding CHANGELOG

If Applicable Checklist

• I have updated the corresponding README(s); local and/or global
• I have added tests that prove my fix is effective or that my feature works
• I have added, or updated, mermaid.js diagrams in the corresponding README(s)
• I have added, or updated, documentation and mermaid.js diagrams in shared/docs/* if I updated shared/*README(s)

[Olshansk]

Prob need to update this now

[deblasis]

@Olshansk PTAL take a look at the short documentation I have added because of the comments in #440

If it's good enough I'll merge 🙏

[Olshansk]

Awesome documentation, ty!