Merge commit '6771781ae' into oct23av

This COMPLETES the merging of the current usptream.master into oct23av
It adds the following commits by Stefan and myself (PRs madgraph5#778 madgraph5#779)
6771781       Andrea Valassi  Thu Oct 26 20:16:42 2023 +0200  Merge pull request madgraph5#779 from valassi/ghav_minorfixes
59922dd       Andrea Valassi  Thu Oct 26 17:58:55 2023 +0200  [oct23av] in CODEGEN MatrixElementKernels.cc, fix clang-format after cherry-picking Olivier's 9fc9873
040f574       Andrea Valassi  Thu Oct 26 13:06:20 2023 +0200  [oct23av] in CODEGEN, improve comments to generated code for mirror processes (see PR madgraph5#754)
7564f04       Andrea Valassi  Thu Oct 26 20:06:29 2023 +0200  Merge pull request madgraph5#778 from valassi/ghav_gqttqref
d9c3fae       Andrea Valassi  Thu Oct 26 17:19:24 2023 +0200  [oct23av] in CODEGEN, update gqttq ref file for runTest after fixing coupling order in PR madgraph5#757
c803581       Stefan Roiser   Thu Oct 26 17:46:11 2023 +0200  sync submodule