fix: allow hapi plugin from array to be registered as argument

[dmathieu]

Which problem is this PR solving?

I missed this in #1046.
HAPI plugins can be registered directly as objects, with server.register(plugin). But they can also be registered as an array, with server.register([plugin]).

Right now, we only accept server.register([{plugin: plugin}]);, which doesn't match the hapi documentation.
See https://hapi.dev/tutorials/plugins/?lang=en_US#loading

Short description of the changes

Allow registering hapi plugins from an array when the object is passed directly, and they are not nested within a deeper object.

[codecov]

Codecov Report

Merging #1253 (bc53a9d) into main (180b336) will increase coverage by 3.10%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1253      +/-   ##
==========================================
+ Coverage   96.08%   99.19%   +3.10%     
==========================================
  Files          14        5       -9     
  Lines         893      247     -646     
  Branches      191       36     -155     
==========================================
- Hits          858      245     -613     
+ Misses         35        2      -33     

Impacted Files	Coverage Δ
...emetry-instrumentation-hapi/src/instrumentation.ts	99.31% <100.00%> (ø)
...umentation-user-interaction/src/instrumentation.ts
...etapackages/auto-instrumentations-web/src/utils.ts
...entation-document-load/src/enums/AttributeNames.ts
...metry-propagator-aws-xray/src/AWSXRayPropagator.ts
...lugin-react-load/src/BaseOpenTelemetryComponent.ts
...metry-propagator-ot-trace/src/OTTracePropagator.ts
...lemetry-instrumentation-document-load/src/utils.ts
...y-instrumentation-long-task/src/instrumentation.ts
...erator-aws-xray/src/internal/xray-id-generation.ts
... and 10 more

[dmathieu]

Failing browser test seems unrelated to the changes in this PR.