Workaround to find private Rec files with new CMake configuration

MooreCache uses a file from Rec that is not installed.

Although that was common practice with the CMT and the old-style CMake configuration, it should not be done and if a file in Rec is supposed to be used by downstream projects it should be installed.

This is a kind of temporary workaround, taking into account that when using the new Gaudi configuration classes we should replace options directories with importable Python modules, implicitly fixing the problem of not installed option files.

added lhcb-new-cmake label

• [2021-06-16 00:52] Validation started with lhcb-new-cmake#297
• [2021-06-17 00:48] Validation started with lhcb-new-cmake#298
• [2021-06-18 00:46] Validation started with lhcb-new-cmake#299
• [2021-06-19 00:47] Validation started with lhcb-new-cmake#300
• [2021-06-21 00:37] Validation started with lhcb-new-cmake#301
• [2021-06-22 00:43] Validation started with lhcb-new-cmake#302
• [2021-06-23 00:47] Validation started with lhcb-new-cmake#303
• [2021-06-24 00:33] Validation started with lhcb-head-2#278
• [2021-06-24 00:45] Validation started with lhcb-new-cmake#304
• [2021-06-25 00:26] Validation started with lhcb-head-2#279
• [2021-06-25 00:48] Validation started with lhcb-new-cmake#305
• [2021-06-26 00:49] Validation started with lhcb-new-cmake#306
• [2021-06-28 01:00] Validation started with lhcb-new-cmake#307
• [2021-06-28 11:57] Validation started with lhcb-new-cmake#308
• [2021-06-28 15:23] Validation started with lhcb-new-cmake#309
• [2021-06-28 16:12] Validation started with lhcb-new-cmake#310
• [2021-06-29 00:48] Validation started with lhcb-new-cmake#311
• [2021-06-29 07:23] Validation started with lhcb-new-cmake#312
• [2021-06-29 09:41] Validation started with lhcb-new-cmake#313
• [2021-06-29 12:56] Validation started with lhcb-new-cmake#314
• [2021-06-30 00:30] Validation started with lhcb-head#2986
• [2021-06-30 00:51] Validation started with lhcb-new-cmake#315
• [2021-06-30 10:57] Validation started with lhcb-head#2987
• [2021-07-01 00:20] Validation started with lhcb-head#2988
• [2021-07-01 00:44] Validation started with lhcb-new-cmake#316

added lhcb-head-2 label

removed lhcb-head-2 label

added lhcb-head label

approved this merge request

added Build modernisation labels

assigned to @ziyiw

merged

mentioned in commit 89f5f8c6

mentioned in issue #296 (closed)