RFR: Add "logging in hotspot" to the TODO

[Ludvig Janiuk]

Logging is an undocumented area that is confusing for new developers. Help us do it right.

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Commit messages:
 - Add "logging in hotspot" to the TODO

Changes: https://git.openjdk.java.net/guide/pull/69/files
 Webrev: https://webrevs.openjdk.java.net/?repo=guide&pr=69&range=00
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/guide/pull/69.diff
  Fetch: git fetch https://git.openjdk.java.net/guide pull/69/head:pull/69

PR: https://git.openjdk.java.net/guide/pull/69