[BUG-FIX] T Gate missng in RZ Gate definition

[isolatedinformation]

Issue Description

For both Fraction(1,2) and Fraction(1,4), the to_clifford_plus_t() method decomposes the RZ rotation to the S gate for both the fractions, instead of decomposing to the S and T gates respectively. This PR fixes this :)

How to Reproduce

Code Snippet

TEST_RZ_GATE = """OPENQASM 2.0;
include "qelib1.inc";
qreg q0[4];
h q0[3];
barrier q0[0],q0[1],q0[2],q0[3];
rz(pi/2) q0[1];
rz(pi/4) q0[0];
"""


circ = GatesCircuit().from_qasm(TEST_RZ_GATE)
print("Gate Sequence before conversion to Clifford+T")
for gate in circ.gates:
    print(gate)
print("\nGate sequence after conversion to Clifford T ")
for gate in circ.to_clifford_plus_t().gates:
    print(gate)

Error Output

Gate Sequence before conversion to Clifford+T
H(target_qubit=3)
RZ(target_qubit=1, phase=Fraction(1, 2))
RZ(target_qubit=0, phase=Fraction(1, 4))

Gate sequence after conversion to Clifford T
H(target_qubit=3)
S(target_qubit=1)
S(target_qubit=0)

Corrected Output (in this pr)

Gate Sequence before conversion to Clifford+T
H(target_qubit=3)
RZ(target_qubit=1, phase=Fraction(1, 2))
RZ(target_qubit=0, phase=Fraction(1, 4))

Gate sequence after conversion to Clifford T
H(target_qubit=3)
S(target_qubit=1)
T(target_qubit=0)

[isolatedinformation]

So pytest did not pick this up as an error because the test classes were defined with the name GateTest instead ofTestGate
https://stackoverflow.com/questions/34363388/pytest-no-tests-ran! Added fixes for the tests also

[isolatedinformation]

@gwwatkin @alexnguyenn The test actions for pytest did not run properly for this! I stopped it after it ran for 20 minutes

[gwwatkin]

@isolatedinformation did you run pytest --update-snapshot?

[gwwatkin]

And yes we need to fix this, when certain long snapshots don't match it seems to hang, but that is the whole point of snapshot tests, they check for regressions.

@alexnguyenn can we set a timeout for a couple minutes?

[isolatedinformation]

yeah i did run to update the snapshot and tests ran locally, it just did not on the actions

[gwwatkin]

@isolatedinformation I think you need to commit the changes to the snapshot files, I don't see any of them changed in the diff

[codecov]

Codecov Report

Merging #273 (165561c) into dev (d59f447) will increase coverage by 0.08%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #273      +/-   ##
==========================================
+ Coverage   71.89%   71.98%   +0.08%     
==========================================
  Files          31       31              
  Lines        2288     2288              
==========================================
+ Hits         1645     1647       +2     
+ Misses        643      641       -2     

Impacted Files	Coverage Δ
src/lsqecc/gates/gates.py	100.00% <100.00%> (+4.08%)	⬆️

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