v3: sample_types: [ field name ] loses focus when trying to add a new field

[gnomicosuw]

repro:

1. go to http://localhost:3000/sample_types/new
2. try typing in the [ field name ] field result: the field loses focus with every key on the keyboard expected result: the field should not lose focus

workaround: to get "abc" you need to do the following

• click in the field
• type "a"
• click in the field
• type "b"
• click in the field
• type "c"

and note that you cannot leave trailing spaces when appending to the field, so in order to get "a c" you need to do the following

• click in the field
• type "a"
• click in the field
• type "c"
• click in the field and put the cursor after the "a"
• type