Add CollectionExpression support to CA1870 (UseSearchValues)

[MihaZupan]

Followup after #6898 to add recognition for collection expression patterns as well.

Currently, if you write something like

private static readonly char[] s_chars = new[] { 'a', 'e', 'i', 'o', 'u', 'A' };
public static int Test(ReadOnlySpan<char> s) => s.IndexOfAny(s_chars);

you will be offered two fixers: one to replace s_chars with SearchValues.Create("aeiouA"), and the other to replace the array creation with ['a', 'e', 'i', 'o', 'u', 'A'].
If you accept the latter, you won't be offered the SearchValues fixer anymore since we don't recognize the pattern.

This PR adds recognition for patterns like

static readonly char[] s_chars = ['a', 'e', 'i', 'o', 'u', 'A'];

text.IndexOfAny(['a', 'e', 'i', 'o', 'u', 'A']);
text.IndexOfAny([(byte)'a', (byte)'e', (byte)'i', (byte)'o', (byte)'u', (byte)'A']);
text.IndexOfAny(s_chars);

[MihaZupan]

cc: @stephentoub

[codecov]

Codecov Report

Attention: Patch coverage is 86.82171% with 17 lines in your changes are missing coverage. Please review.

Project coverage is 96.47%. Comparing base (de3a920) to head (3692f88).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##             main    #7252     +/-   ##
=========================================
  Coverage   96.47%   96.47%             
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  Files        1436     1440      +4     
  Lines      342881   344487   +1606     
  Branches    11292    11340     +48     
=========================================
+ Hits       330797   332356   +1559     
- Misses       9230     9262     +32     
- Partials     2854     2869     +15     

[MihaZupan]

@dotnet/roslyn-analysis who would be the right person to review this one?

[buyaa-n]

LGTM, I will let @CyrusNajmabadi take another look

[CyrusNajmabadi]

Looks reasonable to me :-)