Improve error reporting for pyqasm

[TheGupta2012]

Summary of changes

• Improve the error messages across the repository and reduce traceback size
• Added a flag expand_traceback to validate and unroll commands. Set to False by default, it collapses the traceback to only display the last error msg. If set to True, full traceback displayed
• Added exact lines for QASM errors, eg. -

import pyqasm
qasm = """
OPENQASM 3.0;
include "stdgates.inc";

def test(qubit[2] q2, int[32] b) -> bool{
    h q2[0];
    cx q2[0], q2[1];
    return true;
}
qubit[10] q;
bool b = test(a, 5);

"""
program = pyqasm.loads(qasm)
program.unroll(expand_traceback=0)

Output -

ERROR:pyqasm: Error at line 11, column 9 in QASM file

 >>>>>> test(a, 5)

pyqasm.exceptions.ValidationError: Expecting qubit argument for 'q2'. Qubit register 'a' not found for function 'test'
Usage: test ( qubit[2] q2 , int[32] b )

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 97.24138% with 4 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/pyqasm/exceptions.py	80.95%	4 Missing ⚠️

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