Rotate does not work well on partly initialized record ofs, set ofs, and arrays
## Summary
According to Section 7.1.7 of the TTCN-3 standard, "When the rotate operator is used for record of-s, set of-s and arrays, its left hand operand shall be at least partially initialized." However, it does not work, only with fully initialized data elements.
## Steps and/or TTCN-3 code to reproduce
```
type record of integer ROI;
type set of integer SOI;
testcase rotatopsub() runs on ct_empty{
var integer uiarray[3], rot_uiarray[3];
uiarray[0] := 1;
uiarray[2] := 3;
var ROI uiro, rot_uiro;
uiro[0] := 1;
uiro[2] := 3;
var SOI uiso, rot_uiso;
uiso[0] := 1;
uiso[2] := 3;
rot_uiarray := uiarray @> 2;
rot_uiro := uiro @> 2;
rot_uiso := uiso @> 2;
/* if(rot_uiarray[0].isbound){setverdict(pass);}else{setverdict(fail);}
if(rot_uiro[0].isbound){setverdict(pass);}else{setverdict(fail);}
if(rot_uiso[0].isbound){setverdict(pass);}else{setverdict(fail);}
*/
}
```
## What is the current bug behavior?
Runtime error, and after uncommenting the last 3 rows, compile error.
## What is the expected correct behavior?
Pass.
## Relevant logs and/or screenshots
```
MTC@HUL21014: Dynamic test case error: Assignment of an unbound integer value.
```
## Possible fixes
## Titan version
8.1.0
## Platform details (OS type and version)
Microsoft Windows 10 Enterprise 10.0.19042
/cc @aknappqwt @mmagyari
issue