gpl1+ gpl2+ false detection

### Description

Some of the gpl1 rules matches very few text and have
probability to match real code.

for example:

```src/licensedcode/data/rules/gpl-1.0-plus_50.RULE```

only contains 'gpl1+'

On some of my scanned code, I have some variable named i_gpl1, which is incremented in a for loop, so several occurence of

```i_gpl1++```

scancode matches this as gpl-1.0-plus with a score of 100.

I also have another variable named i_gpl2, which also gets incremented, and the rule

```src/licensedcode/data/rules/gpl-2.0-plus_188.RULE``` will match it as gpl-2.0-plus