[FIX] website: restore vertical alignement for half/full height snippets

Commit [1] broke the vertical alignement for half/full height snippets
while trying to improve it. Mentioned commit's goal is kept: not
messing up the alignement when enabling the scroll button and allowing
those height and scroll options for the big boxes snippets, but now
the content is still vertically centered (with or without scroll button
now). If the user do not want it centered, he still has the possibility
to increase the bottom padding.

[1]: https://github.com/odoo/odoo/commit/9d5cd2c1747488524c107e6165d7c55d74b80606

Part of https://github.com/odoo/odoo/pull/58192

closes odoo/odoo#58214

X-original-commit: 08154fb956b4983187eebc3116975772da7b95c4
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/website/static/src/scss/website.scss

@@ -448,9 +448,13 @@ table.table_desc tr td {
 }
 
 .o_full_screen_height {
+    display: flex;
+    flex-direction: column;
+    justify-content: space-around;
     min-height: 100vh !important;
 }
 .o_half_screen_height {
+    @extend .o_full_screen_height;
     min-height: 55vh !important;
 }
 

addons/website/static/src/snippets/s_color_blocks_2/000.scss

@@ -1,10 +1,16 @@
 .s_color_blocks_2 {
-    display: flex; // Needed to be able to stretch the inner container so that
-                   // the snippet works with the 50% and 100% height
+    // Needed to be able to stretch the inner container so that
+    // the snippet works with the 50% and 100% height
+    &.o_half_screen_height, &.o_full_screen_height {
+        > :first-child { // container
+            &, > .row {
+                min-height: inherit;
+            }
+        }
+    }
     .row {
         display: flex;
         flex-flow: row wrap;
-        height: 100%; // Needed for the 50% and 100% height option
 
         // Fix for safari browser as it 'supports' flex but not with the right
         // behavior