fldigi: Update to 4.2.06

[vk1kcm]

Description

• Update to version 4.2.06 maintenance release

Type(s)

• bugfix
• enhancement
• security fix

Tested on

macOS 15.2 24C101 arm64
Xcode 16.2 16C5032a

Verification

Have you

• followed our Commit Message Guidelines?
• checked that there aren't other open pull requests for the same change?
• referenced existing tickets on Trac with full URL in commit message?
• checked your Portfile with port lint?
• tried existing tests with sudo port test?
• tried a full install with sudo port -vst install? (-t doesn't work on aarch64)
• tested basic functionality of all binary files?
• checked that the Portfile's most important variants haven't been broken?

[macportsbot]

Notifying maintainers:
@ra1nb0w for port fldigi.

[ra1nb0w]

LGTM. Thank you very much!!