try render and check for pdflatex

[Polkas]

closes #89

• Add a validation if the pdflatex is installed, if not raise an error.
• try call around the render call.
• rm sprintf where not needed.

tested with podman run --rm -p 8787:8787 -e PASSWORD=yourpasswordhere rocker/rstudio as it not contains pdflatex by default.

[github-actions]

Unit Tests Summary

    1 files    17 suites   10s ⏱️
186 tests 186 ✔️ 0 💤 0 ❌
268 runs  268 ✔️ 0 💤 0 ❌

Results for commit 203f9c1.

♻️ This comment has been updated with latest results.

[github-actions]

Code Coverage Summary

Filename              Stmts    Miss  Cover    Missing
------------------  -------  ------  -------  -------------------------------------------------------------------------
R/AddCardModule.R       100       3  97.00%   75-77
R/Archiver.R             25       0  100.00%
R/ContentBlock.R         16       0  100.00%
R/DownloadModule.R      161      40  75.16%   77-79, 100, 150-155, 164-168, 171-175, 183-187, 190-194, 201-205, 208-212
R/FileBlock.R            13       0  100.00%
R/NewpageBlock.R          2       0  100.00%
R/PictureBlock.R         30       1  96.67%   15
R/Previewer.R           217      11  94.93%   162, 164-167, 172-178
R/Renderer.R             54       4  92.59%   142, 144-145, 166
R/ReportCard.R           76       2  97.37%   211, 232
R/Reporter.R             96       1  98.96%   255
R/ResetModule.R          45       0  100.00%
R/SimpleReporter.R       18       0  100.00%
R/TableBlock.R            8       0  100.00%
R/TealReportCard.R       20       0  100.00%
R/TextBlock.R            13       0  100.00%
R/yaml_utils.R           74       2  97.30%   65, 263
TOTAL                   968      64  93.39%

Results for commit: cdb97cd

Minimum allowed coverage is 80%

♻️ This comment has been updated with latest results

[mhallal1]

Looks fine to me after the fix of system2 and works as expected.
I did not test it with an environment without pdflatex as my docker is not very happy therefore I will leave it to be approved by someone who could test this. @junlueZH ?
@npaszty I believe you had this issue also so it would be great if you could test this PR locally?

[mhallal1]

I followed with @Polkas shared screen how he tested this on a the docker image above and it worked as expected.