chore(snap): refactor PeerAndModeDecidingSyncState and SnapshotSyncIntegrationTest

[Vovchyk]

Description

Motivation and Context

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• Tests for the changes have been added (for bug fixes / features)
• Requires Activation Code (Hard Fork)

• Other information:

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
70.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[fmacleal]

Nice refactor. :)
LGTM