Return noop instrument if name is invalid

[jack-berg]

Resolves #4378.

I think returning a noop instrument is the least wrong solution:

• Throwing an exception is not in line with API patterns
• If we log a warning but allowed the invalid name to be used, we'd put the burden on exporters to figure out how to handle metrics that break the rules.
• If we log a warning an transform the name to be valid, we'd be making up unspecified rules, and could cause unexpected conflicts with other metrics.

[codecov]

Codecov Report

Merging #4383 (5bfd124) into main (c2d8f6a) will increase coverage by 0.05%.
The diff coverage is 100.00%.

❗ Current head 5bfd124 differs from pull request most recent head 31d80b0. Consider uploading reports for the commit 31d80b0 to get more accurate results

@@             Coverage Diff              @@
##               main    #4383      +/-   ##
============================================
+ Coverage     89.94%   90.00%   +0.05%     
- Complexity     4908     4920      +12     
============================================
  Files           567      567              
  Lines         15199    15219      +20     
  Branches       1465     1465              
============================================
+ Hits          13671    13698      +27     
+ Misses         1058     1051       -7     
  Partials        470      470              

Impacted Files	Coverage Δ
.../io/opentelemetry/api/internal/ValidationUtil.java	100.00% <100.00%> (ø)
...ava/io/opentelemetry/api/metrics/DefaultMeter.java	100.00% <100.00%> (ø)
...in/java/io/opentelemetry/sdk/metrics/SdkMeter.java	100.00% <100.00%> (ø)
...emetry/api/baggage/propagation/PercentEscaper.java	84.21% <0.00%> (+4.51%)	⬆️
...ava/io/opentelemetry/sdk/internal/RateLimiter.java	100.00% <0.00%> (+5.88%)	⬆️

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