tests: remove unnecessary v_printf test

vlib/strconv/format.md

@@ -3,7 +3,7 @@
 These are v implementations of the C language `printf` and `sprintf` functions.
 
 > **Note**
-> These functions are platform dependent in C, but in V they are platform independent.
+> These functions are deprecated and will be removed soon. Use string interpolation instead.
 
 ### v_sprintf
 

vlib/v/parser/parser.v

@@ -193,10 +193,8 @@ pub fn (mut p Parser) set_path(path string) {
 	p.file_display_path = os.real_path(p.file_name).replace_once(parser.normalised_working_folder,
 		'').replace('\\', '/')
 	p.inside_vlib_file = p.file_name_dir.contains('vlib')
-	p.inside_test_file = p.file_base.ends_with('_test.v')
-		|| p.file_base.ends_with('_test.vv')
+	p.inside_test_file = p.file_base.ends_with('_test.v') || p.file_base.ends_with('_test.vv')
 		|| p.file_base.all_before_last('.v').all_before_last('.').ends_with('_test')
-		|| (p.file_name_dir.contains('vlib/v/slow_tests/inout/') && p.file_base.ends_with('.vv'))
 
 	hash := fnv1a.sum64_string(path)
 	p.unique_prefix = hash.hex_full()

vlib/v/slow_tests/inout/strconv_v_printf.vv

@@ -1,40 +0,0 @@
-import strconv
-
-const limit = 201
-
-fn main() {
-	// sieve
-	mut c := [limit]bool{}
-	c[1] = true
-
-	mut p := 2
-	for {
-		p2 := p * p
-		if p2 >= limit {
-			break
-		}
-
-		for i := p2; i < limit; i += p {
-			c[i] = true
-		}
-
-		for {
-			p++
-			if !c[p] {
-				break
-			}
-		}
-	}
-
-	// sieve complete.  now print a representation.
-	for n in 1 .. limit {
-		if c[n] {
-			print('  .')
-		} else {
-			strconv.v_printf('%3d', n)
-		}
-		if n % 20 == 0 {
-			println('iter: ${n}')
-		}
-	}
-}