bug(ios): Shavian keyboard freezes when typing third character

### Describe the bug


when typing the third shavian character (doesn’t matter which one), keyman freezes.

### Reproduce the bug

Go to any text box on iOS
Try to type three shavian characters

### Expected behavior

I can continue typing without the keyboard freezing

### Related issues

_No response_

### Keyman apps

- [ ] Keyman for Android
- [X] Keyman for iPhone and iPad
- [ ] Keyman for Linux
- [ ] Keyman for macOS
- [ ] Keyman for Windows
- [ ] Keyman Developer
- [ ] KeymanWeb
- [ ] Other - give details at bottom of form

### Keyman version

16.0.139

### Operating system

iOS 16.4.1 (a)

### Device

iphone 8 plus

### Target application

every text box on iOS

### Browser

_No response_

### Keyboard name

_No response_

### Keyboard version

_No response_

### Language name

Shavian (English)

### Additional context

_No response_