rekeyTo check missing checks at beginning of code

tealer dev branch commit: 403cff3abc48c5cd65f1c62048d455223fe6e4a0

The following code appears to be ignored and Tealer insists the smart contract contract can be rekeyed, yet the very first instructions are:
```
#pragma version 5
txn RekeyTo
global ZeroAddress
!=
txn CloseRemainderTo
global ZeroAddress
!=
||
txn AssetCloseTo
global ZeroAddress
!=
||
bnz main_l104

....

main_l104:
int 0
return
```

I end up getting about 2380 rekey_to errors in fact, even though it's literally the first thing checked.