[Glitch] Ensure tabIndex is number instead of string

Port ec0c104bf2 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/features/pinned_accounts_editor/index.jsx

@@ -59,7 +59,7 @@ class PinnedAccountsEditor extends ImmutablePureComponent {
             {accountIds.map(accountId => <AccountContainer key={accountId} accountId={accountId} added />)}
           </div>
 
-          {showSearch && <div role='button' tabIndex='-1' className='drawer__backdrop' onClick={onClear} />}
+          {showSearch && <div role='button' tabIndex={-1} className='drawer__backdrop' onClick={onClear} />}
 
           <Motion defaultStyle={{ x: -100 }} style={{ x: spring(showSearch ? 0 : -100, { stiffness: 210, damping: 20 }) }}>
             {({ x }) =>