Pytorch-lightning: self.log on validation_step is broken on pre 1.1 [nightly]

[annikabrundyn]

https://colab.research.google.com/drive/1tSphAIaCdy3tC9Lzhe1GEK_fH_0a6oYj?usp=sharing

[github-actions[bot]]

Hi! thanks for your contribution!, great first issue!

[Borda]

@annikabrundyn mind write here a bit more description as it will be useful for others who have the same problem in the future as the linked colab won't be available always... pls copy-paste the model and TB PrintScreen 🐰

[Borda]

just tested and it appears only on master, the latest 1.0.7rc0 is fine...

[annikabrundyn]

@Borda thank you for looking at this so quickly! will remember to paste context in addition to colab link next time 😊