large-r.should-get: Make the test POSIX compliant

The for i in {x..y} construct is Bash-specific. An alternative would have
been for i in $(seq x y) but seq comes from GNU and is therefore not POSIX. A
good old-fashioned while does the job!

Fixes #3197

algo/tests/should-get-tests/large-r.should-get

-!LAUNCH: (for i in {1..100000}; do echo '>read' ; echo ccgtgtattactgtgcgagagagctgaatacttccagcactg ; done ;) > same-igh-100k.fa ; $LAUNCHER $VIDJIL_DIR/$EXEC $VIDJIL_DEFAULT_OPTIONS -g $VIDJIL_DIR/germline/homo-sapiens.g:IGH -r 5000  -w 15  same-igh-100k.fa; rm -f same-igh-100k.fa
+!LAUNCH: (i=1; while [ $i -le 100000 ]; do echo '>read' ; echo ccgtgtattactgtgcgagagagctgaatacttccagcactg ; i=$((i+1)); done ;) > same-igh-100k.fa ; $LAUNCHER $VIDJIL_DIR/$EXEC $VIDJIL_DEFAULT_OPTIONS -g $VIDJIL_DIR/germline/homo-sapiens.g:IGH -r 5000  -w 15  same-igh-100k.fa; rm -f same-igh-100k.fa
 
 $ Find a unique clone with all reads
 1:>clone-001--IGH--0100000--100.--window