Axis match bug

[richmanpoorman]

Link to issue

Closes #5427

Description of change

• Bug was that function marked the axis to be connected, but the trace_kwargs still had unique axes
• Change: change the keyword argument for the trace, so that when the graph is initialized, it uses the correct axis instead of the autogenerated one
• Note: The program generates a unique axis label for each subgraph, and then overwrites the label (under this fix)

Demo

Testing strategy

Used this test code to see if the line showed up; since this is a visibility test, no unit tests were provided

`# Create sample data
df = pd.DataFrame({
'x': pd.date_range('2024-01-01', periods=100),
'y1': range(100),
'y2': [x**2 for x in range(100)]
})

Create subplots

fig = make_subplots(
rows=2, cols=1,
shared_xaxes=True,
vertical_spacing=0.02
)

fig.add_trace(go.Scatter(x=df['x'], y=df['y1'], name='Line 1'), row=1, col=1)
fig.add_trace(go.Scatter(x=df['x'], y=df['y2'], name='Line 2'), row=2, col=1)

fig.update_traces(xaxis='x2')

fig.update_xaxes(
showspikes=True,
spikemode='across',
spikesnap='cursor',
spikecolor='black',
spikethickness=1
)

fig.update_layout(hovermode='x unified')
fig.show()`

Additional information (optional)

This is my first pull request, so please let me know if there is anything

Guidelines

• I have reviewed the pull request guidelines and the Code of Conduct and confirm that this PR follows them.
• I have added an entry to the changelog if needed (not required for documentation PRs).