[MulitSelect] Move showOpenerLabelAsText out of sharedProps (#2379)

## Summary:
Follow up from #2354 the new `showOpenerLabel` was included in the `sharedProps`  in the MultiSelect that are passed to the SelectOpener which caused many unit tests to fail when trying to update the dropdown package in webapp (Khan/webapp#27791)

Issue: XXX-XXXX

## Test plan:
Install the snapshot in webapp, yarn test

Author: daniellewhyte

Reviewers: beaesguerra

Required Reviewers:

Approved By: beaesguerra

Checks: ✅ Chromatic - Get results on regular PRs (ubuntu-latest, 20.x), ✅ Test / Test (ubuntu-latest, 20.x, 2/2), ✅ Test / Test (ubuntu-latest, 20.x, 1/2), ✅ Lint / Lint (ubuntu-latest, 20.x), ✅ Check build sizes (ubuntu-latest, 20.x), ✅ Chromatic - Build on regular PRs / chromatic (ubuntu-latest, 20.x), ✅ Publish npm snapshot (ubuntu-latest, 20.x), ⏭️  Chromatic - Skip on Release PR (changesets), ✅ Prime node_modules cache for primary configuration (ubuntu-latest, 20.x), ✅ Check for .changeset entries for all changed files (ubuntu-latest, 20.x), ✅ gerald, ⏭️  dependabot

Pull Request URL: #2379

.changeset/famous-buckets-vanish.md

@@ -0,0 +1,5 @@
+---
+"@khanacademy/wonder-blocks-dropdown": patch
+---
+
+[MultiSelect and SingleSelect] Remove `showOpenerLabelAsText` from sharedProps that are passed to SelectOpener

packages/wonder-blocks-dropdown/src/components/multi-select.tsx

@@ -528,6 +528,7 @@ export default class MultiSelect extends React.Component<Props, State> {
             className,
             "aria-invalid": ariaInvalid,
             "aria-required": ariaRequired,
+            showOpenerLabelAsText,
             /* eslint-enable @typescript-eslint/no-unused-vars */
             ...sharedProps
         } = this.props;

packages/wonder-blocks-dropdown/src/components/single-select.tsx

@@ -398,6 +398,7 @@ export default class SingleSelect extends React.Component<Props, State> {
             placeholder,
             selectedValue,
             testId,
+            showOpenerLabelAsText,
             // the following props are being included here to avoid
             // passing them down to the opener as part of sharedProps
             /* eslint-disable @typescript-eslint/no-unused-vars */
@@ -414,7 +415,6 @@ export default class SingleSelect extends React.Component<Props, State> {
             className,
             "aria-invalid": ariaInvalid,
             "aria-required": ariaRequired,
-            showOpenerLabelAsText,
             ...sharedProps
         } = this.props;