update readme by v1.2.x (#6728)

Author: Borda

README.md

@@ -91,19 +91,6 @@ Lightning is rigurously tested across multiple GPUs, TPUs CPUs and against major
   </center>
 </details>
 
-<details>
-  <summary>Bleeding edge build status (1.2)</summary>
-
-  <center>
-
-  ![CI base testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20base%20testing/badge.svg?branch=release%2F1.2-dev&event=push)
-  ![CI complete testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20complete%20testing/badge.svg?branch=release%2F1.2-dev&event=push)
-  ![PyTorch & Conda](https://github.com/PyTorchLightning/pytorch-lightning/workflows/PyTorch%20&%20Conda/badge.svg?branch=release%2F1.2-dev&event=push)
-  ![TPU tests](https://github.com/PyTorchLightning/pytorch-lightning/workflows/TPU%20tests/badge.svg?branch=release%2F1.2-dev&event=push)
-  ![Docs check](https://github.com/PyTorchLightning/pytorch-lightning/workflows/Docs%20check/badge.svg?branch=release%2F1.2-dev&event=push)
-  </center>
-</details>
-
 ---
 
 ## How To Use
@@ -132,22 +119,22 @@ pip install pytorch-lightning
   conda install pytorch-lightning -c conda-forge
   ```
 
-  #### Install stable - future 1.1.x
+  #### Install stable 1.2.x
 
-  the actual status of 1.1 [stable] is following:
+  the actual status of 1.2 [stable] is following:
 
-  ![CI base testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20base%20testing/badge.svg?branch=release%2F1.1.x&event=push)
-  ![CI complete testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20complete%20testing/badge.svg?branch=release%2F1.1.x&event=push)
-  ![PyTorch & Conda](https://github.com/PyTorchLightning/pytorch-lightning/workflows/PyTorch%20&%20Conda/badge.svg?branch=release%2F1.1.x&event=push)
-  ![TPU tests](https://github.com/PyTorchLightning/pytorch-lightning/workflows/TPU%20tests/badge.svg?branch=release%2F1.1.x&event=push)
-  ![Docs check](https://github.com/PyTorchLightning/pytorch-lightning/workflows/Docs%20check/badge.svg?branch=release%2F1.1.x&event=push)
+  ![CI base testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20base%20testing/badge.svg?branch=release%2F1.2.x&event=push)
+  ![CI complete testing](https://github.com/PyTorchLightning/pytorch-lightning/workflows/CI%20complete%20testing/badge.svg?branch=release%2F1.2.x&event=push)
+  ![PyTorch & Conda](https://github.com/PyTorchLightning/pytorch-lightning/workflows/PyTorch%20&%20Conda/badge.svg?branch=release%2F1.2.x&event=push)
+  ![TPU tests](https://github.com/PyTorchLightning/pytorch-lightning/workflows/TPU%20tests/badge.svg?branch=release%2F1.2.x&event=push)
+  ![Docs check](https://github.com/PyTorchLightning/pytorch-lightning/workflows/Docs%20check/badge.svg?branch=release%2F1.2.x&event=push)
 
   Install future release from the source
   ```bash
-  pip install git+https://github.com/PytorchLightning/pytorch-lightning.git@release/1.1.x --upgrade
+  pip install git+https://github.com/PytorchLightning/pytorch-lightning.git@release/1.2.x --upgrade
   ```
 
-  #### Install bleeding-edge - future 1.2
+  #### Install bleeding-edge - future 1.3
 
   Install nightly from the source (no guarantees)
   ```bash