test(dpkg,apk): exhaustive tests for dpkg extras, fix apk parseInfoNameVersion panic

- dpkg: add normalize_test.go with NormalizeName/ParseArch table tests
- dpkg: add capabilities, DryRunner, interface compliance, parse edge cases
- apk: fix parseInfoNameVersion panic on empty input
- apk: add empty/whitespace test cases for parseInfoNameVersion

807 tests passing, 0 failures.

apk/apk_test.go

@@ -312,6 +312,18 @@ func TestParseInfoNameVersion(t *testing.T) {
 			wantN: "lib-ssl-dev",
 			wantV: "3.0.0-r0",
 		},
+		{
+			name:  "empty",
+			input: "",
+			wantN: "",
+			wantV: "",
+		},
+		{
+			name:  "whitespace_only",
+			input: "   ",
+			wantN: "",
+			wantV: "",
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {