Add recent releases to documentation versions list

Created some branches for those versions according to existing format.
Note that `scylla-4.19.0.x` corresponds to the latest released `4.19.0.1`
and not current master (`scylla-4.x`).
If the next released version is `4.19.0.2` then `scylla-4.19.0.x` will need to
be moved with whatever documentation backports it has on top of `4.19.0.2`.
However it's unlikely that `4.19.0.2` would not have the same changes already,
so it should not be an issue.

Author: Bouncheck

docs/source/conf.py

@@ -22,10 +22,13 @@
     'scylla-4.12.0.x',
     'scylla-4.13.0.x',
     'scylla-4.14.1.x',
-    'scylla-4.15.0.x'
+    'scylla-4.15.0.x',
+    'scylla-4.17.0.x',
+    'scylla-4.18.1.x',
+    'scylla-4.19.0.x'
 ]
 # Set the latest version.
-LATEST_VERSION = 'scylla-4.15.0.x'
+LATEST_VERSION = 'scylla-4.19.0.x'
 # Set which versions are not released yet.
 UNSTABLE_VERSIONS = []
 # Set which versions are deprecated
@@ -99,6 +102,9 @@
     'scylla-4.13.0.x',
     'scylla-4.14.1.x',
     'scylla-4.15.0.x',
+    'scylla-4.17.0.x',
+    'scylla-4.18.1.x',
+    'scylla-4.19.0.x'
 ]
 suppress_warnings = ["ref.any", "myst.header","myst.xref_missing","autosectionlabel"]