Fix indentation and closing-paren placement for multi-resource try-with-resources

[saloni-eng]

Fixes #1392.

Try-with-resources statements with more than one resource were
formatting inconsistently: the first resource stayed glued to try (,
and the closing ) was glued to the last resource, e.g.:

try (var input = Files.newInputStream(Path.of("./input"));
    var output = Files.newOutputStream(Path.of("./output")); ) {

This changes multi-resource try statements to break after (, put
each resource on its own line, and place the closing ) back at the
same indentation as try, matching how other multi-line constructs
(e.g. argument lists) are formatted:

try (
    var input = Files.newInputStream(Path.of("./input"));
    var output = Files.newOutputStream(Path.of("./output"))) {

Single-resource try-with-resources statements are unaffected.

Changes

• JavaInputAstVisitor.visitTry: conditionally open a plusFour
  indent and force a break after ( only when there's more than one
  resource; close the indent level before the trailing break so the
  closing ) renders at the outer indent instead of the resource
  indent.
• FormatterTest: added multivariableTryWithResources covering the
  new formatting.
• testdata/B21465217.output, testdata/B26159561.output: regenerated
  golden files that encoded the old (pre-fix) multi-resource layout.

Testing

mvn clean test passes, including the CR/LF/CRLF idempotency checks
in FormatterIntegrationTest.

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