Previous cell wrongly executed

[cgahr]

If the cursor is at the start of the line before the # denoting the start of a cell, the previous cell is executed instead of the cell starting with this line.

Example:

# %%
print(1)

|# %%
print(2)

The bar | represents the position of the cursor. In the example, the first cell is executed and the output is 1, but it should be 2.

[sschuhmann]

Fixed with your PR. Thank you!