auto yaml and other utils

[Polkas]

closes #11

The as_yaml_auto function, validation and conversion of a flat list (like shiny input) to the nested and proper one.

• if many layers list then yaml::as.yaml directly
• if a one layer list then we could assign fields automatically

why we need this as_yaml_auto function as shiny inputs return flat list
After this function is established we could introduce custom yaml header fields in the Download Modules
#26

Other helpful yaml utils were added.

[nikolas-burkoff]

A couple of small comments from me - I've certainly not done a full review

[github-actions]

Unit Tests Summary

    1 files    13 suites   7s ⏱️
126 tests 126 ✔️ 0 💤 0 ❌
170 runs  170 ✔️ 0 💤 0 ❌

Results for commit a2d7d6d.

♻️ This comment has been updated with latest results.

[github-actions]

Code Coverage Summary

Filename              Stmts    Miss  Cover    Missing
------------------  -------  ------  -------  -------------------------------
R/AddCardModule.R        75       3  96.00%   53-55
R/ContentBlock.R         16       0  100.00%
R/DownloadModule.R      134       5  96.27%   77-79, 100, 154
R/NewpageBlock.R          2       0  100.00%
R/PictureBlock.R         31       0  100.00%
R/Renderer.R             54       8  85.19%   142, 144-145, 155-157, 164, 166
R/ReportCard.R           43       0  100.00%
R/Reporter.R             17       0  100.00%
R/SimpleReporter.R       12       0  100.00%
R/TableBlock.R            9       0  100.00%
R/TealReportCard.R        9       0  100.00%
R/TextBlock.R             7       0  100.00%
R/yaml_utils.R           74       2  97.30%   66, 265
TOTAL                   483      18  96.27%

Results for commit: 6047740

Minimum allowed coverage is 80%

♻️ This comment has been updated with latest results

[Polkas]

I just apply the function in the Download module