pgAdmin 4 commit: 1) Enable the 'Configure' and 'View log' menu option

1) Enable the 'Configure' and 'View log' menu option when the server taking longer than usual time to start.
2) When an error occurs from the backend, the configure window opens and if the user has changed the setting
of the port, it won't take any effect as we have retrieved the value of the port at the start of the runtime.
3) Added logic to identify the specified fixed port is already in use. Throw the error before starting the pgAdmin server.

Fixes #5751

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=59649ca42cfc6156110d50011792d6d92721f02f

Modified Files
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docs/en_US/release_notes_4_26.rst | 1 +
runtime/FloatingWindow.cpp | 15 +++-
runtime/FloatingWindow.h | 2 +
runtime/Runtime.cpp | 181 +++++++++++++++++++++++++-------------
runtime/Runtime.h | 16 ++--
runtime/TrayIcon.cpp | 15 +++-
runtime/TrayIcon.h | 2 +
7 files changed, 163 insertions(+), 69 deletions(-)