[std] Reorder clauses: [algorithm], [strings]

Part of the C++26 clause restructuring (#5315).

Author: tkoeppe

source/std.tex

@@ -129,11 +129,11 @@
 \include{memory}
 \include{meta}
 \include{utilities}
-\include{strings}
 \include{containers}
 \include{iterators}
 \include{ranges}
 \include{algorithms}
+\include{strings}
 \include{numerics}
 \include{time}
 \include{locales}