[projmgr] Rework warning message for device/board deprecation (#953)

[grasci-arm]

Address https://github.com/Open-CMSIS-Pack/devtools/issues/1598

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 63.56%. Comparing base (319f991) to head (39d7a43).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1601 +/- ## ======================================= Coverage 63.56% 63.56% ======================================= Files 162 162 Lines 31295 31295 Branches 19180 19180 ======================================= Hits 19894 19894 + Misses 7533 7531 -2 - Partials 3868 3870 +2 ``` | [Flag](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack) | Coverage Δ | | |---|---|---| | [projmgr-cov](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack) | `80.47% <100.00%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack#carryforward-flags-in-the-pull-request-comment) to find out more. | [Files](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack) | Coverage Δ | | |---|---|---| | [tools/projmgr/src/ProjMgrYamlParser.cpp](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601?src=pr&el=tree&filepath=tools%2Fprojmgr%2Fsrc%2FProjMgrYamlParser.cpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack#diff-dG9vbHMvcHJvam1nci9zcmMvUHJvak1ncllhbWxQYXJzZXIuY3Bw) | `81.01% <100.00%> (ø)` | | | [tools/projmgr/test/src/ProjMgrUnitTests.cpp](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601?src=pr&el=tree&filepath=tools%2Fprojmgr%2Ftest%2Fsrc%2FProjMgrUnitTests.cpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack#diff-dG9vbHMvcHJvam1nci90ZXN0L3NyYy9Qcm9qTWdyVW5pdFRlc3RzLmNwcA==) | `79.41% <100.00%> (ø)` | | ... and [2 files with indirect coverage changes](https://app.codecov.io/gh/Open-CMSIS-Pack/devtools/pull/1601/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Open-CMSIS-Pack)

[github-actions[bot]]

Test Results

    3 files     18 suites   6m 58s :stopwatch:   344 tests   344 :white_check_mark: 0 :zzz: 0 :x: 1 032 runs  1 032 :white_check_mark: 0 :zzz: 0 :x:

Results for commit 39d7a438.