Added missing plus sign in CbmDataLinkDef

The change is necessary to allow writing std::vector<CbmHit> to the output tree. Otherwise cryptic error messages are produced by ROOT. This was discovered while transitioning from TClonesArray to std::vector<CbmTrdHit> in the TRD hitfinder.

Luckily this was already encountered and discussed by @fweig here: https://github.com/root-project/root/issues/10240

Otherwise it would probably have taken me ages to figure this out....

Maybe also of interest to @p.-a.loizeau @se.gorbunov @s.zharko

On edit: Not sure whether this change produces problems elsewhere.

added BugFix label

requested review from @f.uhlig

assigned to @v.friese

changed the description

Dear @f.uhlig, @v.friese, @p.-a.loizeau,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label

approved this merge request

added 2 commits

• 76676049 - 1 commit from branch computing:master
• 12d57a50 - Added missing plus sign in CbmDataLinkDef.

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added 39 commits

• 12d57a50...f4ca4341 - 38 commits from branch computing:master
• 5dfe6fd7 - Added missing plus sign in CbmDataLinkDef.

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merged