Docs: list $spam_ variables in expansions chapter
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-rw-r--r-- 63 .exim-project-root
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drwxr-xr-x - .github
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-rw-r--r-- 1916 .mailmap
-rw-r--r-- 2316 Readme.pod
-rw-r--r-- 1104 SECURITY.md
drwxr-xr-x - configs
drwxr-xr-x - doc
drwxr-xr-x - release-process
drwxr-xr-x - src
drwxr-xr-x - test