CQL: Property names starting with "A" or "An" are parsed wrongly after WITH
## Summary
E.g. a query like `FIND Analysis WITH analysis_type=something` is parsed to
```sql
<ParseTree>(cq Find (entity Analysis) (entity_filter (which_exp with an) (filter_expression (pov (property alysis_type) = (value (atom something))))) <EOF>)</ParseTree>
```
i.e., the `WITH analysis_type` is split into `WITH AN alysis_type`. So the `which_exp` parser seems to be too greedy here.
## Expected Behavior
It should parse correctly to `WITH analysis_type`
## Actual Behavior
Parses to `WITH AN alysis_type` instead leading to empty queries.
## Steps to Reproduce the Problem
1. Simply type any query containing `WITH <property starting with A or An>` and look at the parse tree in the server response.
## Specifications
- Version: caosdb-server v0.10.0
- Platform: any
## Workaround
Add an `A` or `AN` to the expression. I.e., `FIND Analysis WITH AN analysis_type=something` is parsed correctly.
issue