Test builds with later Tensorflow Lite releases

[phlash]

TFLite are now up to 2.6.1 (stable) and beyond in testing releases: https://github.com/tensorflow/tensorflow/releases

These may offer fixes for newer toolchains (GCC 11+, Clang 12+), in particular on more bleeding edge distros such as Manjaro.

Ticket here is to try these later versions of TFLite against newer toolchains, and ensure backscrub still actually works 😄

See also: #93

[phlash]

Manjaro, GCC 11.1.0: TFLite v2.6.0 - builds ok 👍
Debian (stable), GCC 10.2.0: TFLite v2.6.0 - build ok 👍 , runs ok 👏

PR #121 covers the change - would appreciate others testing on their distro.

[BenBE]

Updated main and experimental to TFLite 2.6.0: works fine on Lubuntu 20.04 LTS for me, no obvious regressions.

Didn't test with any more recent TFLite releases.

[cypMon]

Manjaro, GCC 11.1.0: TFLite v2.6.0 - builds ok

Probably doesn't help a lot, but builds and runs great under Arch Linux with the same versions.

[BenBE]

What might be interesting is if the code still works properly with the upcoming 2.7 release.

[jjsarton]

Ferora, GCC 12.1.1: TFLite v2.8.0 - builds ok