Update renovate/renovate Docker tag to v34.21.4

This MR contains the following updates:

Package	Type	Update	Change
renovate/renovate	image	minor	34.20.4 -> 34.21.4

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Release Notes

renovatebot/renovate

v34.21.4

Miscellaneous Chores

• Revert "chore: process labels on pull requests" (#​18838) (9111a6b)

Documentation

• Add pnpm-lock.yaml to supported lock files (#​18844) (53c4120)
• regex: improve link name (#​18841) (29c12e6)

Build System

• deps: update dependency @​opentelemetry/instrumentation-bunyan to v0.30.1 (#​18846) (9b5dd8c)

v34.21.3

Bug Fixes

• manager/gradle: prefix version catalog aliases with "libs." (#​18830) (fb56b1f)

Miscellaneous Chores

• process labels on pull requests (#​18836) (39a1b47)

v34.21.2

Build System

• deps: update dependency redis to v4.4.0 (#​18832) (a820a8a)

v34.21.1

Bug Fixes

• datasource/sbt-package: Fallbacks to maven when no sbt directory listing available (#​18590) (8433ad9)

Documentation

• asdf: rewrite readme (#​18795) (64ddabc)

v34.21.0

Features

• versioning/nixpkgs: add nixpkgs versioning (#​18817) (f73b133)

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