fixes a bug which introduces erroneous entries in mers_vector when computing minstrobes

[blinard-BIOINFO]

@ksahlin

Incorrect if Condition in Index Generation for minstrobes

Description:
An incorrect if condition leads to errors during the index generation for minstrobes, resulting in incorrect values. @marouaneboumlik98 (our student) found that changing the comparison is enough to fix the bug.

Impact:
This causesd incorrect index generation, affecting the accuracy of mapping results.

To reproduce: use version before the fix, attached files, and the following commands:

Command Used: ./StrobeMap -k 10 -n 2 -v 11 -w 15 -c minstrobes -o mapped.tsv ref.fa read.fa

As shown in the result file allMersVector.csv on lines 1, 2, and 14.

Hash value	RefID	Pos strobe 1	Pos strobe 2	Pos strobe 3
9863	0	54	497928	497928
49626	0	55	497928	497928
103236	0	44	55	55
105440	0	46	59	59
106712	0	42	54	54
115443	0	5	19	19
163407	0	31	44	44
169210	0	19	31	31
169631	0	3	17	17
175292	0	13	25	25
179254	0	39	53	53
179837	0	17	31	31
184950	0	25	39	39
202716	0	56	497928	497928
204796	0	53	65	65
205123	0	30	44	44
215534	0	2	13	13
228731	0	1	13	13
232695	0	28	39	39
237749	0	29	42	42
261466	0	16	30	30
272296	0	51	63	63
278894	0	6	19	19
284876	0	11	25	25
295497	0	45	59	59
312866	0	34	46	46
361799	0	52	63	63
363599	0	0	13	13
366845	0	12	25	25
369158	0	33	44	44
370175	0	37	51	51
371847	0	40	54	54
387185	0	22	34	34
399836	0	47	59	59
411673	0	7	19	19
415217	0	8	19	19
415943	0	43	54	54
424988	0	41	54	54
451385	0	20	31	31
453038	0	14	25	25
474401	0	4	17	17
494000	0	18	31	31
494722	0	27	39	39
511251	0	50	63	63
520043	0	9	22	22
520245	0	32	44	44
522991	0	23	37	37
528256	0	48	59	59
536163	0	35	46	46
541996	0	49	60	60
546037	0	15	29	29
549875	0	38	51	51
560253	0	26	39	39
578971	0	36	47	47
579274	0	24	37	37
589182	0	10	22	22
612599	0	21	34	34

[ksahlin]

Thank you for the fix! Classic off-by-one error..

i + w_max was allowed to go up to string_hashes.size(); which access an address outside the vector with string_hashes[i + w_max];.