Fix warnings about misleading indentation. (#19186)

Fix warnings about misleading indentation. (#19186)

This is subtle and not actually misleading,
because it tends to be space tab or space tab, not wrong
number of tabs or significant wrong number of spaces.

/s/mono2/mono/metadata/class.c:4010:6: warning: misleading indentation;
      statement is not part of the previous 'if' [-Wmisleading-indentation]
                                 if (mono_class_implement_interface_slo...

/s/mono2/mono/metadata/class.c:4039:3: warning: misleading indentation;
      statement is not part of the previous 'if' [-Wmisleading-indentation]
        if (m_class_is_delegate (target) && mono_class_has_variant_gener...

/s/mono2/mono/mini/driver.c:1780:4: warning: misleading indentation; statement
      is not part of the previous 'if' [-Wmisleading-indentation]
                if (strncmp (argv [i], "--debugger-agent=", 17) == 0) {