Correction of step in test plan

**Problem description**
In some test plans there is a step:
```
And the event header "Authorization" is set to "Bearer: " + ...
```

**Expected behavior**
I must be
In some test plans there is a step:
```
And the event header "Authorization" is set to "Bearer " + ...
```
removing `:`

**Additional context**
Detected in https://github.com/camaraproject/QualityOnDemand/issues/481
