Fix all errcheck linter issues

Co-authored-by: Junie <junie@jetbrains.com>

internal/acme/validate.go

@@ -23,7 +23,7 @@ func (h *Handler) validateChallenge(ctx context.Context, chall *Challenge, accou
 		h.logger.Error("acme: load authz for validation", "id", chall.AuthzID, "error", err)
 		chall.Status = StatusInvalid
 		chall.Error = &ProblemDetail{Type: ProblemServerInternal, Detail: "failed to load authorization"}
-		h.saveChallenge(ctx, chall)
+		_ = h.saveChallenge(ctx, chall)
 		return
 	}
 	// Inject the identifier value into the context for validators.
@@ -202,7 +202,7 @@ func validateHTTP01(ctx context.Context, chall *Challenge, accountJWK []byte) er
 	if err != nil {
 		return fmt.Errorf("HTTP-01 fetch failed: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != http.StatusOK {
 		return fmt.Errorf("HTTP-01: unexpected status %d", resp.StatusCode)