move response xml parser to helper

[individual-it]

Description

move the helper function to parse the content of a response as xml to the helper

Related Issue

part of #33690
fixes #33990

Motivation and Context

simplify WebDav.php trait

How Has This Been Tested?

🤖

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

Open tasks:

• Backport (if applicable set "backport-request" label and remove when the backport was done)

[codecov]

Codecov Report

Merging #33991 into master will increase coverage by 15.61%.
The diff coverage is n/a.

@@              Coverage Diff              @@
##             master   #33991       +/-   ##
=============================================
+ Coverage     48.53%   64.15%   +15.61%     
- Complexity        0    18340    +18340     
=============================================
  Files           109     1198     +1089     
  Lines         10501    69385    +58884     
  Branches       1276     1276               
=============================================
+ Hits           5097    44514    +39417     
- Misses         5035    24502    +19467     
  Partials        369      369

Flag	Coverage Δ	Complexity Δ
#javascript	53.09% <ø> (ø)	0 <ø> (ø)	⬇️
#phpunit	65.43% <ø> (+26.8%)	18340 <ø> (+18340)	⬆️

Impacted Files	Coverage Δ	Complexity Δ
apps/files_external/lib/config.php	10.71% <0%> (-20.87%)	19% <0%> (+19%)
apps/updatenotification/templates/admin.php	0% <0%> (ø)	0% <0%> (?)
lib/private/Encryption/Keys/Storage.php	88.03% <0%> (ø)	48% <0%> (?)
lib/private/App/CodeChecker/NodeVisitor.php	95.86% <0%> (ø)	54% <0%> (?)
lib/private/RedisFactory.php	0% <0%> (ø)	19% <0%> (?)
apps/dav/lib/Avatars/AvatarNode.php	72% <0%> (ø)	9% <0%> (?)
...s/dav/appinfo/Migrations/Version20170202213905.php	21.05% <0%> (ø)	12% <0%> (?)
apps/dav/lib/Upload/ChunkLocationProvider.php	100% <0%> (ø)	4% <0%> (?)
apps/files/lib/AppInfo/Application.php	39.02% <0%> (ø)	7% <0%> (?)
apps/systemtags/list.php	0% <0%> (ø)	0% <0%> (?)
... and 1081 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update bc2ef17...83a3396. Read the comment docs.

[codecov]

Codecov Report

Merging #33991 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master   #33991   +/-   ##
=========================================
  Coverage     64.77%   64.77%           
  Complexity    18340    18340           
=========================================
  Files          1198     1198           
  Lines         69418    69418           
  Branches       1276     1276           
=========================================
  Hits          44964    44964           
  Misses        24085    24085           
  Partials        369      369

Flag	Coverage Δ	Complexity Δ
#javascript	53.09% <ø> (ø)	0 <ø> (ø)	⬇️
#phpunit	66.12% <ø> (ø)	18340 <ø> (ø)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update bc2ef17...83a3396. Read the comment docs.

[individual-it]

backport in #33993