chore(deps): update dependency com.google.code.gson:gson to v2.8.9

[mend-for-github-com]

This PR contains the following updates:

Package	Type	Update	Change
com.google.code.gson:gson	compile	patch	2.8.6 -> 2.8.9

By merging this PR, the issue #139 will be automatically resolved and closed:

Severity	CVSS Score	CVE
High	7.7	WS-2021-0419
High	7.5	CVE-2022-25647

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Release Notes

google/gson

v2.8.9

• Make OSGi bundle's dependency on sun.misc optional (https://github.com/google/gson/pull/1993).
• Deprecate Gson.excluder() exposing internal Excluder class (https://github.com/google/gson/pull/1986).
• Prevent Java deserialization of internal classes (https://github.com/google/gson/pull/1991).
• Improve number strategy implementation (https://github.com/google/gson/pull/1987).
• Fix LongSerializationPolicy null handling being inconsistent with Gson (https://github.com/google/gson/pull/1990).
• Support arbitrary Number implementation for Object and Number deserialization (https://github.com/google/gson/pull/1290).
• Bump proguard-maven-plugin from 2.4.0 to 2.5.1 (https://github.com/google/gson/pull/1980).
• Don't exclude static local classes (https://github.com/google/gson/pull/1969).
• Fix RuntimeTypeAdapterFactory depending on internal Streams class (https://github.com/google/gson/pull/1959).
• Improve Maven build (https://github.com/google/gson/pull/1964).
• Make dependency on java.sql optional (https://github.com/google/gson/pull/1707).

v2.8.8

• Fixed issue with recursive types (https://github.com/google/gson/issues/1390).
• Better behaviour with Java 9+ and Unsafe if there is a security manager (https://github.com/google/gson/pull/1712).
• EnumTypeAdapter now works better when ProGuard has obfuscated enum fields (https://github.com/google/gson/pull/1495).

v2.8.7

• Fixed ISO8601UtilsTest failing on systems with UTC+X.
• Improved javadoc for JsonStreamParser.
• Updated proguard.cfg (https://github.com/google/gson/pull/1693).
• Fixed IllegalStateException in JsonTreeWriter (https://github.com/google/gson/issues/1592).
• Added JsonArray.isEmpty() (https://github.com/google/gson/pull/1640).
• Added new test cases (https://github.com/google/gson/pull/1638).
• Fixed OSGi metadata generation to work on JavaSE < 9 (https://github.com/google/gson/pull/1603).

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