A string with a number could be passed as a boolean value

[stickeerehan]

get_cfg_var() evaluates "true" in php.ini to "1" which is not correctly parsed by the boolean parser.

Fixes issue raised on #1431.

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• ✅ login: stickeerehan / name: Rehan Aslam (db5093d, 745d595)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.57%. Comparing base (8857b0c) to head (745d595).

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1435      +/-   ##
============================================
- Coverage     73.59%   73.57%   -0.03%     
- Complexity     2685     2687       +2     
============================================
  Files           387      387              
  Lines          7977     7981       +4     
============================================
+ Hits           5871     5872       +1     
- Misses         2106     2109       +3     

Flag	Coverage Δ
8.1	?
8.2	?
8.3	?
8.4	73.57% <100.00%> (+0.07%)	⬆️

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Files with missing lines	Coverage Δ
.../SDK/Common/Configuration/Parser/BooleanParser.php	92.85% <100.00%> (+2.85%)	⬆️

... and 4 files with indirect coverage changes

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[brettmc]

Hi @stickeerehan thanks for the contribution. We also need to be compliant with the OpenTelemetry spec as much as possible, and here we run into this part: https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#boolean-value

Any value that represents a Boolean MUST be set to true only by the case-insensitive string "true", meaning "True" or "TRUE" are also accepted, as true. An implementation MUST NOT extend this definition and define additional values that are interpreted as true. Any value not explicitly defined here as a true value, including unset and empty values, MUST be interpreted as false.

Having a quick play with this:
php.ini:

my_bool = true
my_quoted_bool = "true"

$ php -a
Interactive shell

php > var_dump(get_cfg_var('my_bool'));
string(1) "1"
php > var_dump(get_cfg_var('my_quoted_bool'));
string(4) "true"

So, quoting boolean values in php.ini seems to work, and maybe we need to document that?

inadvertent