[FIX] web_kanban: restore elements which broke over 2 lines

Since commit https://github.com/odoo/odoo/commit/577311c0e11edca5740b232881a16dda2ffd32dc,
some elements are now put in a <span/>. This broke the layout in some
cases as the <span/> elements are displayed as blocks in dashboards since
https://github.com/odoo/odoo/commit/a86d6a7df980d55dd0af007f77c6bb039771525a#diff-4b309c73c7896544c509c1374cc3b682R58

As there is no apparent reason for this, this commit fixes the
problem by making these elements have the `inline-block` display.

opw-747119

addons/web_kanban/static/src/less/kanban_dashboard.less

@@ -39,7 +39,7 @@
 
         // If invisible, elem will no take more than its original height
         a, span {
-            .o-text-overflow(block);
+            .o-text-overflow(inline-block);
             position: relative;
         }
 
@@ -88,9 +88,10 @@
 
             .o_kanban_manage_button_section {
                 .o-flex(1, 0, 0);
-                padding: @odoo-horizontal-padding;
 
                 .o_kanban_manage_toggle_button {
+                    display: block;
+                    padding: @odoo-horizontal-padding;
                     text-align: right;
                 }
             }