Fix [MDEP-931] Replace PrintWriter with Writer in AbstractSerializing Visitor and subclasses

[Ndacyayisenga-droid]

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Fixes https://issues.apache.org/jira/browse/MDEP-931

cc @elharo

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[elharo]

CI failing on a known flaky test:

Error:  Failures: 
Error:    TestUnpackMojo.testUnpackOverWriteIfNewer:513 unpackedFile '/var/folders/tp/bfmjfn9s0hd59bm9z80j3mgm0000gn/T/unpack2709761897097392486/outputDirectory/testGroupId-snapshot-2.0-SNAPSHOT-null-jar.txt' lastModified() == 1748599196000: should be different. Actual: 1748599196000
[INFO] 

[jira-importer]

Resolve #1439

[Ndacyayisenga-droid]

@elharo I droped all the stringwiters and wrote straight onto the writer

[github-actions[bot]]

@slawekjaranowski Please assign appropriate label to PR according to the type of change.