Adding aliased import when namespace is already required without alias duplicates

e.g. if this is already present:
```
[lambda.dynamo :refer [->attr ->item ->stack-table from-item]]
```
requiring via: `(dyn|)` using autocomplete will result in:
```
[lambda.dynamo :as dynamo]
[lambda.dynamo :refer [->attr ->item ->stack-table from-item]]
```