fix(deps): update dependency mongoose to v6.0.15

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
mongoose (source)	6.0.14 -> 6.0.15

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Release Notes

Automattic/mongoose (mongoose)

v6.0.15

Compare Source

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• fix(document): avoid overwriting schema methods when creating a new document with new Model() and strict: false #​11001
• fix(document): avoid overwriting top-level document _id with nested _id when strict = false #​10934
• fix(collection): avoid double-calling callback on sync error #​10956
• fix(connection): handle direct connection to uninitialized replica set that then becomes initialized #​10948
• fix(index.d.ts): allow partial updates on subdocuments for defaults #​10947
• fix(index.d.ts): handle buffer type in schema definitions #​11026

Automattic/mongoose (mongoose)

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[coveralls]

Pull Request Test Coverage Report for Build ac9641ac-099e-4c97-9f14-d05ec211b355

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.08%

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Totals
Change from base Build b0bb0a6e-71e0-4feb-a373-e0a70f8ad93b:	0.0%
Covered Lines:	5658
Relevant Lines:	6014

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💛 - Coveralls