Fixed typo in PPO doc (#983)

* Fixed typo

Fixed typo

* Update changelog

Co-authored-by: Antonin Raffin <[email protected]>

Author: francescoluciano

docs/misc/changelog.rst

@@ -28,8 +28,9 @@ Others:
 
 Documentation:
 ^^^^^^^^^^^^^^
-- Fix typo in docstring "nature" -> "Nature" (@Melanol)
-- Add info on split tensorboard logs into (@Melanol)
+- Fixed typo in docstring "nature" -> "Nature" (@Melanol)
+- Added info on split tensorboard logs into (@Melanol)
+- Fixed typo in ppo doc (@francescoluciano)
 
 
 Release 1.6.0 (2022-07-11)
@@ -1014,4 +1015,4 @@ And all the contributors:
 @eleurent @ac-93 @cove9988 @theDebugger811 @hsuehch @Demetrio92 @thomasgubler @IperGiove @ScheiklP
 @simoninithomas @armandpl @manuel-delverme @Gautam-J @gianlucadecola @buoyancy99 @caburu @xy9485
 @Gregwar @ycheng517 @quantitative-technologies @bcollazo @git-thor @TibiGG @cool-RR @MWeltevrede
-@Melanol @qgallouedec
+@Melanol @qgallouedec @francescoluciano

docs/modules/ppo.rst

@@ -8,7 +8,7 @@ PPO
 The `Proximal Policy Optimization <https://arxiv.org/abs/1707.06347>`_ algorithm combines ideas from A2C (having multiple workers)
 and TRPO (it uses a trust region to improve the actor).
 
-The main idea is that after an update, the new policy should be not too far form the old policy.
+The main idea is that after an update, the new policy should be not too far from the old policy.
 For that, ppo uses clipping to avoid too large update.