Infrastructure: set development branch to 4.19.0 (Mudlet#7614)

<!-- Keep the title short & concise so anyone non-technical can
understand it,
     the title appears in PTB changelogs -->
#### Brief overview of PR changes/additions
Set `development` branch to 4.19.0
#### Motivation for adding to Mudlet
So PTBs have the correct version
#### Other info (issues closed, discussion etc)

Co-authored-by: Vadim Peretokin <[email protected]>

CMakeLists.txt

@@ -101,7 +101,7 @@ else()
 endif()
 
 # Set APP_VERSION (update in mudlet.pro as well)
-set(APP_VERSION 4.18.5)
+set(APP_VERSION 4.19.0)
 
 # Set APP_BUILD based on environment variable MUDLET_VERSION_BUILD or default
 if(DEFINED ENV{MUDLET_VERSION_BUILD} AND NOT $ENV{MUDLET_VERSION_BUILD} STREQUAL "")

src/mudlet.pro

@@ -121,7 +121,7 @@ BUILD_COMMIT_TEST = $$lower($$BUILD_COMMIT_TEST)
 
 
 # Set Mudlet version (update in CMakeLists.txt as well)
-VERSION = 4.18.5
+VERSION = 4.19.0
 
 # Set BUILD based on environment variable MUDLET_VERSION_BUILD or default
 BUILD = $$(MUDLET_VERSION_BUILD)