[FIX] website: fix first/last process steps lines not showing after edit

First & last lines are on `i:after`. After editing, the i is replaced by
a span, so the line disappeared.

See https://github.com/odoo/design-themes/commit/cae0a546cb8e671cc2797bf975413bac746a2b08
which is the original themes commit.

opw-2177464

closes odoo/odoo#44082

Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

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

@@ -25,7 +25,7 @@
                     @include o-position-absolute(50%, 0, 0, auto);
                 }
             }
-            &:not(:first-child):not(:last-child) .s_process_step_icon {
+            .s_process_step_icon {
                 span:after {
                     width: 100%;
                 }
@@ -33,19 +33,7 @@
             &:first-child .s_process_step_icon,
             &:last-child .s_process_step_icon {
                 span:after {
-                    width: 1000%;
-                }
-                .fa {
-                    &:after {
-                        content: '';
-                        z-index: -1;
-                        @include o-position-absolute(50%, auto, 0, auto);
-                        width: 100%;
-                        border-top: 1px solid gray('500');
-                    }
-                    &.mx-auto:after {
-                        width: 50%;
-                    }
+                    width: 50%;
                 }
             }
             &:first-child .s_process_step_icon {
@@ -61,15 +49,4 @@
             }
         }
     }
-
-    $s_process_step_line_fw: true;
-
-    @if $s_process_step_line_fw == true {
-        .s_process_step:first-child,
-        .s_process_step:last-child {
-            .s_process_step_icon > span:after {
-                display: none;
-            }
-        }
-    }
 }