refactor(server): Simplify writeNodeValueAttribute #1041

Job	Run time
Debug Build & Unit Tests (gcc)	56s
Debug Build & Unit Tests (gcc, 32bit)	1m 14s
Debug Build & Unit Tests without Subscriptions (gcc)	2m 9s
Debug Build & Unit Tests with Diagnostics (gcc)	46s
Debug Build & Unit Tests with multithreading (gcc)	4m 8s
Debug Build & Unit Tests with Alarms&Conditions (gcc)	14m 8s
Debug Build & Unit Tests (clang)	1m 4s
Debug Build & Unit Tests (tcc)	59s
Encryption (MbedTLS) Build & Unit Tests (gcc)	2m 44s
PubSub Encryption (MbedTLS) Build & Unit Tests (gcc)	48s
PubSub SKS Build & Unit Tests (gcc)	1m 28s
Encryption (OpenSSL) Build & Unit Tests (gcc)	2m 38s
Encryption (LibreSSL) Build & Unit Tests (gcc)	7m 14s
TPM Tool Build	3m 29s
Release Build	1m 20s
Amalgamation Build	1m 12s
Amalgamation Build with Multithreading	1m 16s
Valgrind Build & Unit Tests with MbedTLS (gcc)	1m 14s
Valgrind Build & Unit Tests with OpenSSL (gcc)	1m 25s
Valgrind Examples with MbedTLS (gcc)	1m 36s
Valgrind Examples with OpenSSL (gcc)	1m 16s
Clang Static Analyzer	2m 25s
Build All Companion Specifications	15m 36s
	1h 11m 5s

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