chore(main): release 2.9.1 (googleapis#1078)

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chore(main): release 2.9.0 (googleapis#1071)

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chore(main): release 2.8.0 (googleapis#1063)

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chore(main): release 2.7.0 (googleapis#1036)

🤖 I have created a release *beep* *boop*
---


## [2.7.0](googleapis/google-auth-library-python@v2.6.6...v2.7.0) (2022-06-07)


### Features

* add experimental enterprise cert support ([googleapis#1052](googleapis#1052)) ([dda7dda](googleapis@dda7dda))
* add experimental GDCH support ([googleapis#1022](googleapis#1022)) ([5367aac](googleapis@5367aac))
* Pluggable auth support ([googleapis#995](googleapis#995)) ([62daa73](googleapis@62daa73))


### Bug Fixes

* validate urls for external accounts ([googleapis#1031](googleapis#1031)) ([61b1f15](googleapis@61b1f15))


### Reverts

* pluggable auth support [googleapis#995](googleapis#995) ([googleapis#1039](googleapis#1039)) ([513d999](googleapis@513d999))
* revert experimental GDCH support ([googleapis#1022](googleapis#1022)) ([googleapis#1042](googleapis#1042)) ([c720995](googleapis@c720995))


### Documentation

* fix changelog header to consistent size ([googleapis#1046](googleapis#1046)) ([e64d084](googleapis@e64d084))

---
This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).

chore(main): release 2.6.6 (googleapis#1029)

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chore(main): release 2.6.5 (googleapis#1023)

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chore(main): release 2.6.4 (googleapis#1017)

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chore(main): release 2.6.3 (googleapis#1009)

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chore(main): release 2.6.2 (googleapis#992)

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chore(main): release 2.6.1 (googleapis#973)

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