chore: cleanup integrations package

[achettyiitr]

Description

• Pass config, logger, and stats from the integrations manager constructor.
• Avoid using exported variables.
• Next step, is to move the uploader, loadFileDownloader, and warehouse fields as well into the constructor in order to have a single producer setup.

Notion Ticket

https://www.notion.so/rudderstacks/cleanup-integrations-package-0b45abc8e39b466aa06192eee5910edc?pvs=4

Security

• The code changed/added as part of this pull request won't create any security issues with how the software is being used.

[codecov]

Codecov Report

Patch coverage: 74.31% and project coverage change: -0.22 ⚠️

Comparison is base (cfee014) 68.29% compared to head (56c826d) 68.08%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3635      +/-   ##
==========================================
- Coverage   68.29%   68.08%   -0.22%     
==========================================
  Files         318      318              
  Lines       50382    50364      -18     
==========================================
- Hits        34408    34289     -119     
- Misses      13749    13852     +103     
+ Partials     2225     2223       -2     

Impacted Files	Coverage Δ
warehouse/admin.go	3.03% <0.00%> (ø)
warehouse/identities.go	19.40% <0.00%> (ø)
warehouse/upload.go	64.69% <0.00%> (ø)
...ehouse/integrations/azure-synapse/azure-synapse.go	62.58% <54.71%> (+0.12%)	⬆️
warehouse/integrations/bigquery/bigquery.go	57.58% <56.75%> (+0.09%)	⬆️
warehouse/integrations/mssql/mssql.go	63.98% <65.75%> (+0.11%)	⬆️
...ns/datalake/schema-repository/schema_repository.go	66.66% <66.66%> (ø)
warehouse/integrations/redshift/redshift.go	66.75% <68.85%> (+0.05%)	⬆️
...se/integrations/datalake/schema-repository/glue.go	77.32% <70.00%> (ø)
warehouse/integrations/snowflake/snowflake.go	64.83% <73.75%> (+0.06%)	⬆️
... and 9 more

... and 10 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.