fix(test): unit test failed on GOARCH=386 (#41)

**What this PR does / why we need it**:
To fix the failed test on 32bit platforms

**Which issue(s) this PR resolves**:
Resolves #40 

**Please check the following list**:
- [x]  Does the affected code have corresponding tests, e.g. unit test?
- [ ] Does this introduce breaking changes that would require an
announcement or bumping the major version?
- [ ]  Do all new files have an appropriate license header?

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Signed-off-by: Junjie Gao <[email protected]>

internal/encoding/asn1/ber/ber_test.go

@@ -19,7 +19,7 @@ import (
 )
 
 func TestConvertToDER(t *testing.T) {
-	var testBytes = make([]byte, 0xFFFFFFFF+8)
+	var testBytes = make([]byte, 0x7FFFFFFF)
 	// primitive identifier
 	testBytes[0] = 0x1f
 	testBytes[1] = 0xa0