Merge #13460: doc: Remove note to install all boost dev packages

fa3d39e doc: Remove note to install all boost dev packages (MarcoFalke)

Pull request description:

  Those notes are for systems that are EOL. Also, those instructions would pull in a ton of additional dependencies such as `python2`.

  Can be reviewed with `git diff HEAD~ --word-diff`

Tree-SHA512: 7e379b3f0b7fe88452baed8860438a7867a025e650a265ed0cd5d47076983f4176545b7d96a4b7f25ae9fcb325f0116d909f3ffb6ff2d7573fddd777fe5b4c79

Author: MarcoFalke

doc/build-unix.md

@@ -70,19 +70,7 @@ tuned to conserve memory with additional CXXFLAGS:
 
 Build requirements:
 
-    sudo apt-get install build-essential libtool autotools-dev automake pkg-config libssl-dev libevent-dev bsdmainutils python3
-
-Options when installing required Boost library files:
-
-1. On at least Ubuntu 14.04+ and Debian 7+ there are generic names for the
-individual boost development packages, so the following can be used to only
-install necessary parts of boost:
-
-        sudo apt-get install libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev
-
-2. If that doesn't work, you can install all boost development packages with:
-
-        sudo apt-get install libboost-all-dev
+    sudo apt-get install build-essential libtool autotools-dev automake pkg-config libssl-dev libevent-dev bsdmainutils python3 libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev
 
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