[pitivi/1.0] docs: Simplified instructions for developers

[Alexandru Băluț <alexbalut src gnome org>]

commit 65b939d04cbc091a7d58a1aa935e3f9c04c43039
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Mon Jan 15 09:14:46 2018 +0100

    docs: Simplified instructions for developers
    
    Differential Revision: https://phabricator.freedesktop.org/D1937

 docs/Bug_reporting.md |   13 ++++---------
 1 files changed, 4 insertions(+), 9 deletions(-)
---
diff --git a/docs/Bug_reporting.md b/docs/Bug_reporting.md
index d1b7188..ccb45c5 100644
--- a/docs/Bug_reporting.md
+++ b/docs/Bug_reporting.md
@@ -94,22 +94,17 @@ for i in $(flatpak list | grep org.pitivi.Pitivi | awk '{ print $1 }'); do
 done
 ```
 
-2. Start a shell in the Pitivi bundle environment
-
-(If developping pitivi, make sure to be in the environment before running)
+2. Start a shell in the Pitivi bundle environment.
 
 ```
-if type ptvenv; then
-  ptvenv
-else
-  flatpak run -d --command=bash org.pitivi.Pitivi
-fi
+flatpak run -d --command=bash org.pitivi.Pitivi
 ```
+In the development environment, you do this by running `ptvenv` instead.
 
 3. Start Pitivi inside gdb
 
 ```
-gdb python3 -ex 'run /app/bin/pitivi
+gdb python3 -ex 'run /app/bin/pitivi'
 ```
 
 When Pitivi crashes, run `bt full` to get the backtrace. When Pitivi