Fix read-only warning when creating GO data

[nuno-agostinho]

Fixes #622

May be related with Perl version used. Perl 5.34 returns the following warning: WARNING: Failed to instantiate plugin GO: Modification of a read-only value attempted at /home/meryem/.vep/Plugins/GO.pm line 327.

To avoid this issue, simply get a slice of @$row instead of using splice() that tries to modify the original array.

Test

Try to create GO plugin data with: ./vep --id rs699 --database --plugin GO

[nakib103]

Thanks Nuno, it fixes the issue.

The error - Modification of a read-only value attempted is introduced in splice function in perl 5.28.0.

It says -

splice now throws an exception ("Modification of a read-only value attempted") when modifying a read-only array. Until now it had been silently modifying the array. The new behaviour is consistent with the behaviour of push and unshift. [perl #131000]

under https://perldoc.perl.org/5.28.0/perldelta#Selected-Bug-Fixes