fix GCC 10 compile issue [-Werror=mismatched-new-delete]

[fizwit]

fix issue #134 and #108

[fizwit]

I can not reproduce the MacOS build error with Monterey 12.3.1

fizwit-MBP ivar % src/ivar version
iVar version 1.3.1

g++ --version
Apple clang version 13.1.6 (clang-1316.0.21.2.3)
Target: arm64-apple-darwin21.4.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin

[cmaceves]

addressed in PR #136

[JacobHayes]

I don't think PR #136 covered this (only the call_consensus_pileup error), I'm still getting this issue as of bafc7b9. That PR does mention delete files, but as also noted master has diverged - indeed it now uses free(files). After making the change in this PR, I was able to compile again.

Can this be re-opened and merged? Thanks! I can put together a reproducible example if needed.

[JacobHayes]

I'm not very familiar with cpp, but iiuc delete is a keyword/operator (rather than a function) and since files is an array, I think we might want: delete [] files(?). I'll make a separate PR just in case it is helpful/quicker to merge.