IText異常 NoClassDefFoundError: org/bouncycastle/asn1/ASN1Encodable

根據Itext的版本，查看依賴庫的版本

maven地址：https://mvnrepository.com/artifact/com.itextpdf/itextpdf

    <dependency>
        <groupId>com.itextpdf</groupId>
        <artifactId>itextpdf</artifactId>
        <version>5.3.2</version>
    </dependency>
    <dependency>
        <groupId>org.bouncycastle</groupId>
        <artifactId>bcprov-jdk15on</artifactId>
        <version>1.47</version>
    </dependency>
    <dependency>
        <groupId>org.bouncycastle</groupId>
        <artifactId>bcmail-jdk15on</artifactId>
        <version>1.47</version>
    </dependency>