fix: do not create http clients every 10s

[korniltsev-grafanista]

fixes #230

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After

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[github-actions]

😢 zizmor failed with exit code 14.

Expand for full output

error[excessive-permissions]: overly broad permissions
 --> ./.github/workflows/release.yml:6:3
  |
6 |   contents: write
  |   ^^^^^^^^^^^^^^^ contents: write is overly broad at the workflow level
  |
  = note: audit confidence → High

15 findings (1 ignored, 13 suppressed): 0 unknown, 0 informational, 0 low, 0 medium, 1 high