Use TemporaryFileSystem for precomp dirs

The actual service has no write access to these directories, so it
will fail until you run the bot with required privileges (after that
it's going to run fine). Now every service will have it's own writable
temp precomp directory.

Author: AlexDaniel

services/whateverable@.service

@@ -31,6 +31,8 @@ ReadWritePaths=/home/bisectable/git/whateverable/sandbox
 ReadWritePaths=/home/bisectable/git/whateverable/data
 ReadOnlyPaths=/home/bisectable/git/whateverable/data/builds
 InaccessiblePaths=/home/bisectable/git/whateverable/config.json
+TemporaryFileSystem=/home/bisectable/git/whateverable/lib/.precomp
+TemporaryFileSystem=/home/bisectable/git/whateverable/lib/Whateverable/.precomp
 
 MemoryMax=1.5G
 TasksMax=80