[SampleFDO] Improve stale profile matching by diff algorithm (#87375)

This change improves the matching algorithm by using the diff algorithm,
the current matching algorithm only processes the callsites grouped by
the same name functions, it doesn't consider the order relationships
between different name functions, this sometimes fails to handle this
ambiguous anchor case. For example. (`Foo:1` means a
calliste[callee_name: callsite_location])
```
IR :      foo:1  bar:2  foo:4  bar:5 
Profile :        bar:3  foo:5  bar:6
```
The `foo:1` is matched to the 2nd `foo:5` and using the diff
algorithm(finding longest common subsequence ) can help on this issue.
One well-known diff algorithm is the Myers diff algorithm(paper "An
O(ND) Difference Algorithm and Its Variations∗" Eugene W. Myers), its
variations have been implemented and used in many famous tools, like the
GNU diff or git diff. It provides an efficient way to find the longest
common subsequence or the shortest edit script through graph searching.
There are several variations/refinements for the algorithm, but as in
our case, the num of function callsites is usually very small, so we
implemented the basic greedy version in this change which should be good
enough.
We observed better matchings and positive perf improvement on our
internal services.

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