fix: typo in variable name `excutable_blocks_found` → `executable_blocks_found` across Tools class

This is issue is linked with PR_ID: #492

There's a small typo in the sources/tools/tools.py self.excutable_blocks_found

You may verify this in sources/tools/tools.py at line: 43, line:150, line:151 and line:200

init → self.excutable_blocks_found = False found_executable_blocks() → tmp = self.excutable_blocks_found load_exec_block() → self.excutable_blocks_found = True