feat: add isReadOnly helper for functions

[Dhaiwat10]

Summary

This PR adds a new helper called isReadOnly to the InvokeFunction type that helps users identify if a given function is read-only or not.

Usage

  const isReadOnly = contract.functions.get_count.isReadOnly();

  if (isReadOnly) {
    await contract.functions.get_count().get();
  } else {
    await contract.functions.get_count().call();
  }

Closes #1931

[Dhaiwat10]

@petertonysmith94 @danielbate I've improved the API so that people don't have to pass in arguments to the function just to check if it's read-only or not.

[maschad]

Looks good, I've left some suggestions around wording in the docs.

[maschad]

Great work!

[github-actions]

Coverage Report:

Lines	Branches	Functions	Statements
79.37%(-0.04%)	69.7%(+0.03%)	77.33%(-0.12%)	79.52%(-0.03%)

Changed Files:

Ok	File (✨=New File)	Lines	Branches	Functions	Statements
🔴	packages/abi-coder/src/FunctionFragment.ts	71.01% (-2.12%)	71.42% (+0%)	73.33% (-11.28%)	70.83% (-3.08%)
🔴	packages/abi-coder/src/utils/utilities.ts	98.24% (+0.03%)	90% (+0%)	100% (+0%)	98.36% (+0.06%)
🔴	packages/account/src/predicate/predicate.ts	30% (-1.37%)	35.71% (+0%)	20% (+0%)	30% (-1.37%)
🔴	packages/program/src/contract.ts	78.94% (-6.77%)	83.33% (+0%)	50% (+0%)	78.94% (-1.06%)