Release 6.6.0

• Merge pull request #619 from nestjs/renovate/pin-dependencies (4b5541a)
• fix(deps): pin dependency tslib to 1.10.0 (1db02ea)
• Merge branch 'tuxmachine-feat/federation' (2449d24)
• refactor(): minor improvements, adjust code style (fd4502f)
• fix(): resolve merge conflicts (6d37373)
• Merge pull request #617 from nestjs/renovate/fast-glob-3.x (0d7363a)
• fix(deps): update dependency fast-glob to v3.2.2 (4897074)
• chore(deps): update dependency release-it to v12.6.1 (05a1f98)
• Update README.md (9cbc59f)
• Update README.md (3560e24)
• chore(deps): remove deprecated @types/graphql dependency (48ff69c)
• fix: invert logic for providing your own schema (c8ba590)
• feat: add code-first support for grahql federation (ef2e409)
• fix(federation): allow apollo engine config in gateway (bc4be48)
• fix(federation): use type merger from 'merge-graphql-schemas' (77ae270)
• fix: support for external resolvers (32f395b)
• fix: scalar resolvers (dfa7332)
• fix: support Apollo Graph Manager (a5bf10b)
• fix: add all options for ApolloServer to Gateway (5c6e168)
• fix: export BuildService token (cf87ea7)
• style: cleanup unused imports (5689b21)
• fix: change GatewayModuleOptions interface (1d3ef17)
• build: update apollo federation and gateway (aecc008)
• test: add test for injecting custom buildservice into gateway (c85b139)
• feat: add fastify support to federation and gateway modules (ee32547)
• test: add tests for generating interfaces for federation (3b9175f)
• feat: add async module support to graphql gateway (aba664f)
• test: asynchronous federation module initialisation (ee39632)
• test: add integration test for gateway module (bef82ab)
• test: add integration test for federation module (073a701)
• style: formatting with prettier (3a54832)
• fix(federation): use resolver reference instead of resolver name (5940608)
• fix(federation): filter resolvers predication (63fa587)
• feat(federation): graphql federation module (5948d67)
• feat(federation): graphql federation factory (d98b480)
• feat(federation): graphql gateway module (ded92ce)
• feat(federation): extract metadata reference resolver (b090702)
• refactor(federation): barrels (7a0da24)
• feat(federation): interfaces for gateway module options (7e235f9)
• feat(federation): make getTypesFromPaths method public (2c83518)
• feat(federation): ResolveReference decorator (f2d5950)
• build: import tslib helpers (75df349)
• chore(federation): add deps (c38c853)