fix: wrap defer resp.Body.Close() to satisfy errcheck linter

[DreadPirateRobertz]

Summary

• Wraps defer resp.Body.Close() in internal/quota/keychain.go with func() { _ = resp.Body.Close() }() to satisfy the errcheck linter
• Matches the pattern already used in internal/wasteland/wasteland.go and internal/doltserver/dolthub.go

Test plan

• go build ./... passes
• Single-line change, no behavioral difference

🤖 Generated with Claude Code

[codecov-commenter]

❌ 1 Tests Failed:

Tests completed	Failed	Passed	Skipped
7862	1	7861	35

View the top 1 failed test(s) by shortest run time

github.com/steveyegge/gastown/internal/rig::TestAddRig_UpstreamURL

Stack Traces | 0.06s run time

=== RUN   TestAddRig_UpstreamURL
    manager_test.go:1312: AddRig: Dolt server is not running (required for beads init); start it with 'gt up' or 'gt dolt start'
--- FAIL: TestAddRig_UpstreamURL (0.06s)

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[steveyegge]

Closing as duplicate — this fix was already merged in PR #2233. Thanks for the contribution!