Add fullTextSearch to dropdowns by default (#14694)

This PR adds `fullTextSearch: 'exact'` to most dropdown
invocations meaning that if there is a search box for the
dropdown it will automatically do a fullTextSearch looking
for the provided fragment instead of starting at the beginning

We should consider changing other places that use
`fullTextSearch: true` to `'exact'` because these will be using a
fuzzy-textual search that doesn't necessarily return the
expected results.

Fix #14689

Signed-off-by: Andrew Thornton <art27@cantab.net>

web_src/js/features/gitgraph.js

@@ -74,6 +74,7 @@ export default async function initGitGraph() {
   $('#flow-select-refs-dropdown').dropdown('set selected', dropdownSelected);
   $('#flow-select-refs-dropdown').dropdown({
     clearable: true,
+    fullTextSeach: 'exact',
     onRemove(toRemove) {
       if (toRemove === '...flow-hide-pr-refs') {
         params.delete('hide-pr-refs');