fix(security): add url validation for help chat (#9956)

[saumeya]

closes #9956

Signed-off-by: saumeya saumeyakatyal@gmail.com

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[codecov]

Codecov Report

Base: 47.46% // Head: 45.62% // Decreases project coverage by -1.84% ⚠️

Coverage data is based on head (eb2e57b) compared to base (4a06cb2).
Patch has no changes to coverable lines.

❗ Current head eb2e57b differs from pull request most recent head 071e9d2. Consider uploading reports for the commit 071e9d2 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10417      +/-   ##
==========================================
- Coverage   47.46%   45.62%   -1.84%     
==========================================
  Files         246      236      -10     
  Lines       41885    28699   -13186     
==========================================
- Hits        19879    13093    -6786     
+ Misses      20008    13805    -6203     
+ Partials     1998     1801     -197     

Impacted Files	Coverage Δ
cmpserver/plugin/plugin.go	49.28% <0.00%> (-29.23%)	⬇️
util/kube/kubectl.go	0.00% <0.00%> (-16.67%)	⬇️
util/grpc/errors.go	47.16% <0.00%> (-13.70%)	⬇️
util/git/creds.go	39.87% <0.00%> (-10.45%)	⬇️
applicationset/services/pull_request/github.go	14.00% <0.00%> (-9.95%)	⬇️
util/helm/cmd.go	24.57% <0.00%> (-7.83%)	⬇️
server/notification/notification.go	56.00% <0.00%> (-7.16%)	⬇️
applicationset/generators/pull_request.go	42.85% <0.00%> (-7.15%)	⬇️
util/io/paths.go	68.75% <0.00%> (-7.12%)	⬇️
server/application/terminal.go	12.75% <0.00%> (-6.73%)	⬇️
... and 236 more

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[crenshaw-dev]

Thanks for the PR and for your patience on the review @saumeya!

[saumeya]

@crenshaw-dev is some other change rquired or can this be merged? I can use a variable to validate it - in case magic string is bad practice.

[crenshaw-dev]

Cherry-picked onto release-2.6 for 2.6.3, release-2.5 for 2.5.12, and release-2.4 for 2.4.24.

[woehrl01]

@saumeya @crenshaw-dev This change now results in showing the chat button even though there is no url at all configured