huge refactoring for S3

[Slach]

replace deprecated github.com/aws/aws-sdk-go-v2/feature/s3/manager to github.com/aws/aws-sdk-go-v2/feature/s3/transfermanager, remove S3_BUFFER_SIZE

[coveralls]

Coverage Report for CI Build 27004419729

Coverage decreased (-0.08%) to 64.774%

Details

• Coverage decreased (-0.08%) from the base build.
• Patch coverage: 3 uncovered changes across 1 file (39 of 42 lines covered, 92.86%).
• 25 coverage regressions across 5 files.

Uncovered Changes

File	Changed	Covered	%
pkg/storage/s3.go	42	39	92.86%

Coverage Regressions

25 previously-covered lines in 5 files lost coverage.

File	Lines Losing Coverage	Coverage
pkg/storage/gcs.go	17	54.63%
pkg/backup/create.go	2	74.72%
pkg/backup/list.go	2	57.58%
pkg/clickhouse/clickhouse.go	2	78.86%
pkg/storage/structs.go	2	84.0%

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Coverage Stats

Relevant Lines:	21555
Covered Lines:	13962
Line Coverage:	64.77%
Coverage Strength:	36452.03 hits per line

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💛 - Coveralls