Update the "Rotating a 3D plot" gallery example to show all 3 rotation axes

[scottshambaugh]

PR Summary

This PR builds off of #21426 and updates the rotate-axes3d-sgskip.py example to show rotation about each individual view axis, with annotations. Here is the resulting animation:

3d_rotations.mp4

PR Checklist

Tests and Styling

• [N/A] Has pytest style unit tests (and pytest passes).
• Is Flake 8 compliant (install flake8-docstrings and run flake8 --docstring-convention=all).

Documentation

• [N/A] New features are documented, with examples if plot related.
• [N/A] New features have an entry in doc/users/next_whats_new/ (follow instructions in README.rst there).
• [N/A] API changes documented in doc/api/next_api_changes/ (follow instructions in README.rst there).
• Documentation is sphinx and numpydoc compliant (the docs should build without error).

[scottshambaugh]

Note that the code to generate that .mp4 is slightly different, but produces the same result:

from mpl_toolkits.mplot3d import axes3d
import matplotlib.pyplot as plt
import matplotlib.animation as animation

fig = plt.figure()
ax = fig.add_subplot(projection='3d')

# Grab some example data.
X, Y, Z = axes3d.get_test_data(0.05)

# Plot a basic wireframe.
ax.plot_wireframe(X, Y, Z, rstride=10, cstride=10)

# Set the axis labels
ax.set_xlabel('x')
ax.set_ylabel('y')
ax.set_zlabel('z')

# Define an update function to pass to FuncAnimation
def update_view(frame):
    # Normalize angle to the range [-180, 180] for display
    angle = (frame + 180) % 360 - 180

    # Cycle through rotating the elevation, azimuth, roll, then all
    elev = azim = roll = 0
    if frame <= 360:
        elev = angle
    elif frame <= 360*2:
        azim = angle
    elif frame <= 360*3:
        roll = angle
    else:
        elev = azim = roll = angle
    
    # Update the axis view and title
    ax.view_init(elev, azim, roll)
    plt.title('Elevation: %d°, Azimuth: %d°, Roll: %d°' % (elev, azim, roll))

# Plot the animation
anim = animation.FuncAnimation(fig, update_view, frames=360*4+1, interval=15)
anim.save("3d_rotations.mp4")

[QuLogic]

Please rebase to go over the committed version of #21426.