Remove duplicate exception definitions

[marioevz]

Currently we define TransactionException in two different files:

execution-specs/packages/testing/src/execution_testing/exceptions/exceptions/transaction.py

Lines 8 to 21 in bff0f2e

	@unique
	class TransactionException(ExceptionBase):
	"""
	Exception raised when a transaction is invalid, and thus cannot be
	executed.
	If a transaction with any of these exceptions is included in a block, the
	block is invalid.
	"""
	TYPE_NOT_SUPPORTED = auto()
	"""Transaction type is not supported on this chain configuration."""
	SENDER_NOT_EOA = auto()
	"""Transaction is coming from address that is not exist anymore."""

execution-specs/packages/testing/src/execution_testing/exceptions/exceptions.py

Lines 124 to 137 in bff0f2e

	@unique
	class TransactionException(ExceptionBase):
	"""
	Exception raised when a transaction is invalid, and thus cannot be
	executed.
	If a transaction with any of these exceptions is included in a block, the
	block is invalid.
	"""
	TYPE_NOT_SUPPORTED = auto()
	"""Transaction type is not supported on this chain configuration."""
	SENDER_NOT_EOA = auto()
	"""Transaction is coming from address that is not exist anymore."""

And BlockException also in two different files:

execution-specs/packages/testing/src/execution_testing/exceptions/exceptions/block.py

Lines 8 to 20 in bff0f2e

	@unique
	class BlockException(ExceptionBase):
	"""
	Exception raised when a block is invalid, but not due to a transaction.
	E.g. all transactions in the block are valid, and can be applied to the
	state, but the block header contains an invalid field.
	"""
	TOO_MANY_UNCLES = auto()
	"""Block declares too many uncles over the allowed limit."""
	UNCLE_IN_CHAIN = auto()
	"""Block declares uncle header that is already imported into chain."""

execution-specs/packages/testing/src/execution_testing/exceptions/exceptions.py

Lines 311 to 323 in bff0f2e

	@unique
	class BlockException(ExceptionBase):
	"""
	Exception raised when a block is invalid, but not due to a transaction.
	E.g. all transactions in the block are valid, and can be applied to the
	state, but the block header contains an invalid field.
	"""
	TOO_MANY_UNCLES = auto()
	"""Block declares too many uncles over the allowed limit."""
	UNCLE_IN_CHAIN = auto()
	"""Block declares uncle header that is already imported into chain."""

They should be defined in a single file.

[AnInsaneJimJam]

Hey @marioevz , Can I contribute, Also in which direction should we be moving related to this issue. Like which file to have and which to not.