LineCollection.contains (ab)uses pickradius<=0 as marker for "filled"

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### Bug report

**Bug summary**

When the pickradius of a LineCollection is set to a <=0 value, LineCollection.contains treats the polygon as "closed".

**Code for reproduction**
```python
from matplotlib import pyplot as plt
from matplotlib.collections import LineCollection
from matplotlib.backend_bases import MouseEvent
import numpy as np

fig, axs = plt.subplots(2)

for ax, pr in zip(axs, [0, 10]):
coll = LineCollection([[(0, 0), (1, 0), (0, 1)]])
ax.add_collection(coll)
ax.set(xlim=(-1, 2), ylim=(-1, 2))
coll.set_pickradius(pr)
for x in np.linspace(*ax.get_xlim())[1:-1]:
for y in np.linspace(*ax.get_ylim())[1:-1]:
x1, y1 = ax.transData.transform((x, y))
contained, _ = coll.contains(
MouseEvent("button_press_event", fig.canvas, x1, y1))
ax.plot(x, y, "o", c="g" if contained else "r", ms=1)

plt.show()
```
**Actual outcome**


Note how on the top LineCollection (using pickradius=0), all points "in" the closed polygon are considered "contained".

**Expected outcome**

Only points exactly on the LineCollection are contained for pickradius = 0, no points are contained for pickradius < 0 (consistently with Line2D).

---

The relevant code is in Line2D.contains:
```python
ind = _path.point_in_path_collection(
mouseevent.x, mouseevent.y, pickradius,
transform.frozen(), paths, self.get_transforms(),
offsets, transOffset, pickradius <= 0, # <--- this last argument is "filled"
self._offset_position)
```

**Matplotlib version**

* Operating system: linux
* Matplotlib version: master, likely since a long time ago
* Matplotlib backend (`print(matplotlib.get_backend())`): any
* Python version: 38
* Jupyter version (if applicable): no
* Other libraries: no

Start with LineCollection.contains and compare its behavior with Line2D.contains, especially the call to _path.point_in_path_collection shown in the report. Run the provided reproduction with pickradius values 0, 10, and below 0, then verify that containment matches the stated expected behavior for each value.

Written by the indexing model from the issue text.