dumpling/gcs: fix http client credential problem

[lichunzhu]

What problem does this PR solve?

cherry-pick of pingcap/tidb#29414

What is changed and how it works?

Dumpling will fail to export data to GCS because of a lack of privileges when we set our own HTTP client without specifying transport tls. This PR deletes it.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
  Test dump data with dumpling before/after this commit. Before this commit GCS will return a gcs error "google api: Error 401: anonymous caller does not have storage.object.create access to the Google Cloud Storage object.". After this commit dumpling can successfully dump data to GCS.

Related changes

• Need to cherry-pick to the release branch

Release note

• fix gcs http client credential problem

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• kennytm

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[lichunzhu]

/cherry-pick release-5.2

[ti-chi-bot]

@lichunzhu: once the present PR merges, I will cherry-pick it on top of release-5.2 in the new PR and assign it to you.

In response to this:

/cherry-pick release-5.2

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[lichunzhu]

/cherry-pick release-5.0

[ti-chi-bot]

@lichunzhu: once the present PR merges, I will cherry-pick it on top of release-5.0 in the new PR and assign it to you.

In response to this:

/cherry-pick release-5.0

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[lichunzhu]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 6bcd777

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #396.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #397.