fix: close response body immediately in retry loop (#567)

ObtainClientCredentialsToken: replace defer resp.Body.Close()
inside the retry loop with immediate close after reading the
response. The deferred closures accumulated on each iteration
and bodies were not released until the function returned.

Author: MaxRink

e2e/helpers/auth.go

@@ -566,21 +566,22 @@ func (p *OIDCTokenProvider) ObtainClientCredentialsToken(t *testing.T, ctx conte
 
 		resp, err := httpClient.Do(req)
 		if err == nil {
-			defer func() { _ = resp.Body.Close() }()
 			if resp.StatusCode == http.StatusOK {
 				var tokenResp struct {
 					AccessToken string `json:"access_token"`
 					TokenType   string `json:"token_type"`
 					ExpiresIn   int    `json:"expires_in"`
 				}
 				err = json.NewDecoder(resp.Body).Decode(&tokenResp)
+				_ = resp.Body.Close()
 				require.NoError(t, err, "Failed to decode client_credentials token response")
 				require.NotEmpty(t, tokenResp.AccessToken, "No access_token in client_credentials response")
 				if attempt > 1 {
 					t.Logf("client_credentials token acquired on attempt %d/%d", attempt, maxAttempts)
 				}
 				return tokenResp.AccessToken
 			}
+			_ = resp.Body.Close()
 			lastErr = fmt.Errorf("client_credentials token request failed with status %d", resp.StatusCode)
 		} else {
 			lastErr = fmt.Errorf("client_credentials token request failed: %w", err)