[frontend] fix ISO format for security coverage time period

[antoinemzs]

Proposed changes

• Fix ISO format for encoded periodicity of security coverage simulation scheduling

Related issues

N/A

Checklist

• I consider the submitted work as finished
• I tested the code for its functionality
• I wrote test cases for the relevant uses case (coverage and e2e)
• I added/update the relevant documentation (either on github or on notion)
• Where necessary I refactored code to improve the overall quality

Further comments

[codecov]

Codecov Report

❌ Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 2.51%. Comparing base (26a4bae) to head (c49981c).
⚠️ Report is 557 commits behind head on master.

Files with missing lines	Patch %	Lines
...i-front/src/components/fields/PeriodicityField.tsx	0.00%	3 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (26a4bae) and HEAD (c49981c). Click for more details.

HEAD has 8 uploads less than BASE

Flag	BASE (26a4bae)	HEAD (c49981c)
opencti	6	2
opencti-front	4	2
opencti-graphql	2	0

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #13787       +/-   ##
===========================================
- Coverage   30.65%    2.51%   -28.14%     
===========================================
  Files        2906     2124      -782     
  Lines      192005   109853    -82152     
  Branches    39089    30090     -8999     
===========================================
- Hits        58854     2767    -56087     
+ Misses     133151   107086    -26065     

Flag	Coverage Δ
opencti	2.51% <0.00%> (-28.14%)	⬇️
opencti-front	2.51% <0.00%> (+0.04%)	⬆️
opencti-graphql	?

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[antoinemzs]

@nino-filigran @SouadHadjiat @lndrtrbn hi this is the smallest fix to address a mistake in encoding iso time periods for the STIX interconnection