Some analysis of reported test timing for latest commits.

The main duration changed, introduced in 00fb57d, was adding new tests. The tests are pretty slow as we write files and load and use eval.

I detect this when I made the commit. But I measure with and without the tests and made sure it was just new tests and no regression.

Not sure about the other entries.

Test Timing by Commit (most recent first)

Commit	Duration	Description
`fb8e7ff`	0.338s	cleanup toplevel handling helpers a bit
`dc29cd2`	0.334s	remove some outdated comments
`b2fbbdd`	0.352s	convert-property-key pass through numbers
`2f5ea14`	0.344s	some cleanup after FFI improvements
`07ce86c`	0.344s	Move parsing also to handle-eval-when
`fba404d`	0.353s	Merge pull request #594 from jscl-project/fix-load-eval-toplevel-forms
`9b70601`	0.346s	Remove redundant parsing from special toplevel forms
`cfaf9e4`	0.354s	Remove LOAD mode from compiler.lisp
`a6dc303`	0.346s	Merge CONVERT-1 and CONVERT
`061fd51`	0.357s	Remove unnecessary conversion
`7932149`	0.352s	Remove undefined reference
`209482d`	0.299s	Remove unnecessary binding
`30f54d6`	0.303s	Process toplevel forms separately in the compiler
`fa1c8ae`	0.318s	Evaluate toplevel forms individually in compiler.lisp
`6769c7d`	0.299s	Simplify toplevel handling of expressions
`c4b631f`	0.290s	Fix EVAL
`d5fa2b4`	0.399s	Add LOAD-VERBOSE special var
`630fa97`	CRASH	Remove deprecated OUTPUT HOOK and PLACE arguments to LOAD
`00fb57d`	0.395s	Reorganize compiler to work with compiler-process-mode
`0ba3552`	0.168s	Fix printing of functions name and docstring
`502c762`	0.171s	Trigger deployment of preview branch if an owner comments /preview
`007b931`	0.175s	Try to fix CI issue with pull requests

Performance regression from 007b931 to 07ce86c #597