Add Transaction Metadata AffectedNodes

[nkramer44]

Adds object mappings for transaction metadata AffectedNodes. Each AffectedNode is one of CreatedNode, ModifiedNode, or DeletedNode. Each one of those represents a ledger object in some way -- however, the representation does not always contain all fields of the object. Therefore, I copied all of the LedgerObject classes and renamed them with a Meta prefix, and made all of the fields Optional.

[codecov]

Codecov Report

Merging #429 (1be39d7) into main (050916e) will increase coverage by 0.18%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##               main     #429      +/-   ##
============================================
+ Coverage     90.09%   90.27%   +0.18%     
- Complexity     1385     1416      +31     
============================================
  Files           268      276       +8     
  Lines          4027     4104      +77     
  Branches        332      339       +7     
============================================
+ Hits           3628     3705      +77     
  Misses          279      279              
  Partials        120      120              

Impacted Files	Coverage Δ
...xrpl4j/model/transactions/TransactionMetadata.java	100.00% <ø> (ø)
...odel/jackson/modules/AffectedNodeDeserializer.java	100.00% <100.00%> (ø)
...rpl/xrpl4j/model/jackson/modules/Xrpl4jModule.java	100.00% <100.00%> (ø)
...pl4j/model/transactions/metadata/AffectedNode.java	100.00% <100.00%> (ø)
...j/model/transactions/metadata/MetaCheckObject.java	100.00% <100.00%> (ø)
...ransactions/metadata/MetaDepositPreAuthObject.java	100.00% <100.00%> (ø)
.../model/transactions/metadata/MetaEscrowObject.java	100.00% <100.00%> (ø)
...del/transactions/metadata/MetaLedgerEntryType.java	100.00% <100.00%> (ø)
...el/transactions/metadata/MetaPayChannelObject.java	100.00% <100.00%> (ø)
.../model/transactions/metadata/MetaTicketObject.java	100.00% <100.00%> (ø)