This company probably won't go bankrupt, but the stock is unlikely to go up.If you're holding shares of Walgreens Boots Alliance (WBA -1.74%) in hopes of it turning around promptly, I think that now is the time to cut your losses on the struggling pharmacy chain and allocate your capital elsewhere. Here's why.A common investing thesis for this stock is now deadOne of the criteria that can help an investor decide when to sell a stock is whether the investing thesis they formed as a rationale for buying the s ...