[Metrics SDK] Change boundry type to double for Explicit Bucket Histogram Aggregation, and change default bucket range

[lalitb]

Fixes: #1628, #1629
Irrespective of the aggregation data type (long or double) for values stored in buckets, the boundaries range should be always of type double.

As mentioned in the specs - https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#explicit-bucket-histogram-aggregation

This PR fixes it.

Also, change the default buckets as per specs changes - open-telemetry/opentelemetry-specification#2770 from
0, 5, 10, 25, 50, 75, 100, 250, 500, 1000 to 0, 5, 10, 25, 50, 75, 100, 250, 500, 750, 1000, 2500, 5000, 7500, 10000

[codecov]

Codecov Report

Merging #1626 (e3da361) into main (9e87a6e) will decrease coverage by 0.01%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1626      +/-   ##
==========================================
- Coverage   85.09%   85.08%   -0.00%     
==========================================
  Files         159      159              
  Lines        5001     4991      -10     
==========================================
- Hits         4255     4246       -9     
+ Misses        746      745       -1     

Impacted Files	Coverage Δ
...metry/sdk/metrics/aggregation/aggregation_config.h	100.00% <ø> (ø)
...nclude/opentelemetry/sdk/metrics/data/point_data.h	100.00% <ø> (ø)
exporters/ostream/src/metric_exporter.cc	91.81% <100.00%> (-0.32%)	⬇️
exporters/ostream/test/ostream_metric_test.cc	100.00% <100.00%> (ø)
...k/src/metrics/aggregation/histogram_aggregation.cc	87.63% <100.00%> (-0.12%)	⬇️
sdk/src/trace/batch_span_processor.cc	90.63% <0.00%> (-0.78%)	⬇️
...metry/nostd/internal/absl/types/internal/variant.h	71.56% <0.00%> (+0.39%)	⬆️

[esigo]

LGTM
Thanks for the PR :)

[esigo]

could you please add #1629 and #1628 to the PR description.

[lalitb]

could you please add #1629 and #1628 to the PR description.

Thanks added.