[fips140][configtls.TestTPM_tpmCertificate_errors] Skip test if GODEBUG=fips140=only is set (open-telemetry#14255)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description

In open-telemetry#14225, we skipped the `configtls.TestTPM_loadCertificate` unit test
if the tests were run with `GODEBUG=fips140=only`. Otherwise, the unit
test failed with a `panic: crypto/cipher: use of CFB is not allowed in
FIPS 140-only mode` error.

Turns out there was a second unit test in the same package that needed
skipping for the same reason: `configtls.TestTPM_tpmCertificate_errors`.
This PR skips it too.

<!-- Issue number if applicable -->
#### Link to tracking issue
Follow up to open-telemetry#14225

Author: ycombinator

config/configtls/tpm_test.go

@@ -101,6 +101,7 @@ func TestTPM_loadCertificate_error(t *testing.T) {
 }
 
 func TestTPM_tpmCertificate_errors(t *testing.T) {
+	testutil.SkipIfFIPSOnly(t, "use of CFB is not allowed in FIPS 140-only mode")
 	tpm, err := simulator.OpenSimulator()
 	require.NoError(t, err)
 	defer tpm.Close()