Code comments improvements (#15722)

- Right-align the Reply and Resolve buttons
- Center Resolved text and add some padding
- Add padding to inline comments
- Indent the comment content to align with author name
- Re-parent form to allow better button layout space.

Co-authored-by: zeripath <art27@cantab.net>

web_src/less/_base.less

@@ -469,6 +469,10 @@ a.ui.card:hover,
   border-top-color: var(--color-secondary-light-1) !important;
 }
 
+.ui.comments .comment .text {
+  margin: 0;
+}
+
 .ui.comments .comment .text,
 .ui.comments .comment .author {
   color: var(--color-text);
@@ -1633,6 +1637,11 @@ a.ui.label:hover {
   border-color: var(--color-light-border);
 }
 
+.ui.labeled.icon.buttons > .button > .icon,
+.ui.labeled.icon.button > .icon {
+  background: var(--color-hover);
+}
+
 .ui.blue.button,
 .ui.blue.buttons .button,
 .ui.primary.button,