Typos (dotnet/corefx#32625)

* Obejct -> Object

* Oberserver -> Observer

* objetcs -> objects

* observeable -> observable

* obsolated -> obsoleted

* occour -> occur

* occurance -> occurrence

* occures -> occurs

* occuring -> occurring

* occurrance -> occurrence

Signed-off-by: dotnet-bot <dotnet-bot@microsoft.com>

src/System.Private.CoreLib/shared/System/Globalization/CalendricalCalculationsHelper.cs

@@ -393,7 +393,7 @@ internal static long PersianNewYearOnOrBefore(long numberOfDays)
 
             double approx = EstimatePrior(LongitudeSpring, MiddayAtPersianObservationSite(date));
             long lowerBoundNewYearDay = (long)Math.Floor(approx) - 1;
-            long upperBoundNewYearDay = lowerBoundNewYearDay + 3; // estimate is generally within a day of the actual occurrance (at the limits, the error expands, since the calculations rely on the mean tropical year which changes...)
+            long upperBoundNewYearDay = lowerBoundNewYearDay + 3; // estimate is generally within a day of the actual occurrence (at the limits, the error expands, since the calculations rely on the mean tropical year which changes...)
             long day = lowerBoundNewYearDay;
             for (; day != upperBoundNewYearDay; ++day)
             {